{"id":2371,"date":"2026-08-27T05:44:47","date_gmt":"2026-08-27T05:44:47","guid":{"rendered":"https:\/\/photo-detector.com\/?p=2371"},"modified":"2026-08-27T05:44:53","modified_gmt":"2026-08-27T05:44:53","slug":"sensor-de-posicion-de-escaner-laser","status":"publish","type":"post","link":"https:\/\/photo-detector.com\/es\/laser-scanner-position-sensor\/","title":{"rendered":"Integraci\u00f3n de fotodiodos segmentados como sensor de posici\u00f3n del esc\u00e1ner l\u00e1ser para impresi\u00f3n 3D SLS y SLM"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">If you have ever had a 72-hour selective laser melting (SLM) run fail at hour 68 because the parts on the outer edges of the build plate warped or shifted by 60 microns, you know how painful thermal drift is. In industrial additive manufacturing, maintaining sub-20-micron repeatability across days of continuous laser firing is a huge engineering hurdle. The scan head absorbs heat radiating from the melt pool, galvanometer drive coils dump heat internally during aggressive vector acceleration, and preheated powder chambers\u2014often sitting above 180\u00b0C in SLS\u2014create massive thermal gradients.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Most industrial scan heads rely on internal feedback to keep mirrors pointing exactly where the controller commands. When that feedback shifts due to chamber heat, your dimensional accuracy falls apart. This is why upgrading your optical <strong>laser scanner position sensor<\/strong> architecture using high-stability segmented photodiodes is becoming the standard for next-generation machines.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Let&#8217;s dive into how you can design, integrate, and tune a high-precision optical <strong>laser scanner position sensor<\/strong> using segmented silicon PIN photodiodes to eliminate thermal zero-point drift in metal and polymer powder bed fusion systems.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">The Thermal Drift Problem in Multi-Day SLS &amp; SLM Builds<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">In additive manufacturing equipment built to meet <strong><a href=\"https:\/\/www.iso.org\/standard\/74514.html\" target=\"_blank\" rel=\"noreferrer noopener\">ISO\/ASTM 52900 standards<\/a><\/strong>, layer thickness frequently ranges from 20 \u00b5m up to 100 \u00b5m. If your laser spot wanders even slightly halfway through a long build cycle, you end up with visible layer stepping, poor surface roughness, or outright structural delamination.<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p class=\"wp-block-paragraph\"><strong>The Thermal Drift Cascade in Galvo Scanners:<\/strong><br>Build Chamber Ambient Heating \u2192 Galvo Drive Coil Resistance Rise \u2192 Sensor Bridge Thermal Imbalance \u2192 False Zero-Point Offset \u2192 Physical Laser Spot Placement Error on Powder Bed<\/p>\n<\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\">Most industrial galvanometer scan heads track position using one of three methods:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Capacitive position detectors<\/li>\n\n\n\n<li>Optical moving-scale digital encoders<\/li>\n\n\n\n<li>Optical analog detectors using split or segmented photodiodes<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Capacitive sensors remain common because they are compact, but their dielectric constant changes as the surrounding temperature climbs. When the scan head housing heats up from 25\u00b0C at machine startup to 55\u00b0C during peak sintering, the baseline capacitance drifts. That drift looks like real mirror movement to the servo loop. The driver tries to &#8220;correct&#8221; this phantom movement, steering the processing laser off target.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A dedicated optical <strong>laser scanner position sensor<\/strong> built around a balanced segmented photodiode isolates position tracking from these dielectric shifts. By measuring an auxiliary optical beam bouncing off a rotor vane or the back face of the mirror, an optical <strong>laser scanner position sensor<\/strong> provides a mechanical reference point that stays stable across long runtimes.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">Comparing Galvo Position Sensing Technologies<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Choosing the best feedback technology comes down to balancing your build envelope, scan speed, and thermal environment. Here is how position sensing options compare inside high-temperature additive manufacturing machines:<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th>Sensing Technology<\/th><th>Typical Thermal Drift (\u00b5rad\/K)<\/th><th>Bandwidth \/ Step Response<\/th><th>Temperature Sensitivity<\/th><th>Inertia Impact on Rotor<\/th><\/tr><\/thead><tbody><tr><td><strong>Capacitive Feedback<\/strong><\/td><td>15 \u2013 40<\/td><td>Very High (&lt; 150 \u00b5s)<\/td><td>High (dielectric shifts with ambient heat)<\/td><td>Zero (non-contact plate)<\/td><\/tr><tr><td><strong>Digital Optical Scale<\/strong><\/td><td>2 \u2013 5<\/td><td>Moderate (&lt; 300 \u00b5s)<\/td><td>Low (requires precise thermal glass scales)<\/td><td>High (adds rotor mass)<\/td><\/tr><tr><td><strong>Segmented Diode Position Sensor<\/strong><\/td><td>1 \u2013 3<\/td><td>Very High (&lt; 100 \u00b5s)<\/td><td>Extremely Low (differential ratio cancels drift)<\/td><td>Negligible (tiny reflective vane)<\/td><\/tr><tr><td><strong>Open-Loop (No Feedback)<\/strong><\/td><td>&gt; 200<\/td><td>N\/A<\/td><td>Extreme (unusable for industrial AM)<\/td><td>None<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">While digital optical encoders deliver high resolution, their bulky glass scales add rotational inertia to the galvanometer rotor, which slows down your jump speeds and vector hatch rates. An optical <strong>laser scanner position sensor<\/strong> based on segmented photodiodes gives you low rotational inertia combined with near-zero thermal drift.<\/p>\n\n\n\n<div data-block-name=\"woocommerce\/single-product\" data-product-id=\"2234\" data-wp-context=\"woocommerce\/products::{&quot;productId&quot;:2234,&quot;variationId&quot;:null}\" data-wp-interactive=\"woocommerce\/single-product\" class=\"wp-block-woocommerce-single-product woocommerce\">\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-7387b849 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<div data-block-name=\"woocommerce\/product-gallery\" 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height=\"24\" aria-hidden=\"true\" focusable=\"false\">\n\t\t\t\t\t\t\t<path d=\"M13 11.8l6.1-6.3-1-1-6.1 6.2-6.1-6.2-1 1 6.1 6.3-6.5 6.7 1 1 6.5-6.6 6.5 6.6 1-1z\"><\/path>\n\t\t\t\t\t\t<\/svg>\n\t\t\t\t\t<\/button>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"wc-block-product-gallery-dialog__content\">\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<img\n\t\t\t\t\t\t\t\tdata-image-id=\"2235\"\n\t\t\t\t\t\t\t\tdata-wp-watch=\"callbacks.toggleImageVisibility\"\n\t\t\t\t\t\t\t\tsrc=\"https:\/\/photo-detector.com\/wp-content\/uploads\/2026\/06\/PDC-C2929-scaled.webp\"\n\t\t\t\t\t\t\t\tsrcset=\"https:\/\/photo-detector.com\/wp-content\/uploads\/2026\/06\/PDC-C2929-scaled.webp 2560w, https:\/\/photo-detector.com\/wp-content\/uploads\/2026\/06\/PDC-C2929-300x300.webp 300w, https:\/\/photo-detector.com\/wp-content\/uploads\/2026\/06\/PDC-C2929-1024x1024.webp 1024w, https:\/\/photo-detector.com\/wp-content\/uploads\/2026\/06\/PDC-C2929-150x150.webp 150w, https:\/\/photo-detector.com\/wp-content\/uploads\/2026\/06\/PDC-C2929-768x768.webp 768w, https:\/\/photo-detector.com\/wp-content\/uploads\/2026\/06\/PDC-C2929-1536x1536.webp 1536w, https:\/\/photo-detector.com\/wp-content\/uploads\/2026\/06\/PDC-C2929-2048x2048.webp 2048w, https:\/\/photo-detector.com\/wp-content\/uploads\/2026\/06\/PDC-C2929-12x12.webp 12w, https:\/\/photo-detector.com\/wp-content\/uploads\/2026\/06\/PDC-C2929-600x600.webp 600w, https:\/\/photo-detector.com\/wp-content\/uploads\/2026\/06\/PDC-C2929-100x100.webp 100w\"\n\t\t\t\t\t\t\t\tsizes=\"(max-width: 2560px) 100vw, 2560px\"\n\t\t\t\t\t\t\t\tdecoding=\"async\"\n\t\t\t\t\t\t\t\talt=\"PDC-C2929 cost effective 920nm silicon PIN photodiode chip for laser scanner\" \/>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/dialog>\n\t\t<\/div>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-vertically-aligned-center is-layout-flow wp-block-column-is-layout-flow\"><h2 class=\"wp-block-post-title\"><a href=\"https:\/\/photo-detector.com\/es\/product\/920nm-silicon-pin-photodiode\/\" target=\"_blank\">Si PIN photodiodes for Galvo PDC-C2929<\/a><\/h2>\n\n<div data-block-name=\"woocommerce\/product-summary\" data-is-descendent-of-single-product-block=\"true\" class=\"wp-block-woocommerce-product-summary\"><div class=\"wc-block-components-product-summary \" style=\"\">\n\t\t\t\t<p>The PDC-C2929 is a budget-friendly 920nm silicon PIN photodiode chip. This 920nm silicon PIN photodiode offers stable, cost-effective scanner position tracking.<\/p>\n\n\t\t\t<\/div><\/div>\n\n\n<div data-block-name=\"woocommerce\/product-meta\" class=\"wp-block-woocommerce-product-meta\">\n<div class=\"wp-block-group is-nowrap is-layout-flex wp-container-core-group-is-layout-7387b849 wp-block-group-is-layout-flex\">\n\n<div class=\"taxonomy-product_tag wp-block-post-terms\"><span class=\"wp-block-post-terms__prefix\">Tag\uff1a<\/span><a href=\"https:\/\/photo-detector.com\/es\/product-tag\/920nm-pin-photodiode\/\" rel=\"tag\">920nm PIN Photodiode<\/a><span class=\"wp-block-post-terms__separator\">, <\/span><a href=\"https:\/\/photo-detector.com\/es\/product-tag\/bee-photon\/\" rel=\"tag\">Bee Photon<\/a><span class=\"wp-block-post-terms__separator\">, <\/span><a href=\"https:\/\/photo-detector.com\/es\/product-tag\/budget-photodiode-chip\/\" rel=\"tag\">Budget Photodiode Chip<\/a><span class=\"wp-block-post-terms__separator\">, <\/span><a href=\"https:\/\/photo-detector.com\/es\/product-tag\/galvo-sensor\/\" rel=\"tag\">Galvo Sensor<\/a><span class=\"wp-block-post-terms__separator\">, <\/span><a href=\"https:\/\/photo-detector.com\/es\/product-tag\/silicon-pin-photodiode\/\" rel=\"tag\">Silicon PIN photodiode<\/a><\/div><\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">Operating Principles: How Segmented Photodiodes Track Mirror Angle<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">An optical <strong>laser scanner position sensor<\/strong> operates on a differential measurement principle. Instead of measuring total light intensity, it measures how an auxiliary reference beam splits across two or four isolated photosensitive segments.<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p class=\"wp-block-paragraph\">True position accuracy in high-temperature optomechanics comes from symmetry. When heat expands your mechanical fixtures uniformly, a differential ratiometric measurement cancels out the common-mode error before the signal ever reaches your analog-to-digital converter.<\/p>\n<\/blockquote>\n\n\n\n<h3 class=\"wp-block-heading\">1. Bi-Cell (One-Dimensional) Angular Tracking<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">For a single galvo axis (X or Y mirror), a dual-element (bi-cell) photodiode such as the <strong><a href=\"https:\/\/photo-detector.com\/product\/segmented-pin-photodiode-chip\/\" target=\"_blank\" rel=\"noreferrer noopener\">PDC-2C3432-NIR-B segmented PIN photodiode chip<\/a><\/strong> from <strong><a href=\"https:\/\/photo-detector.com\/\" target=\"_blank\" rel=\"noreferrer noopener\">BeePhoton<\/a><\/strong> provides high-speed one-dimensional tracking.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">An auxiliary LED or VCSEL beam (often 920 nm or 940 nm) passes through a slit mask or focusing lens and hits the boundary between Segment A and Segment B. As the galvo shaft turns, the light spot shifts across the boundary.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The photocurrent generated by each segment is converted to a voltage via transimpedance amplifiers (TIAs):<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Position Signal (Delta X) = (V_A &#8211; V_B) \/ (V_A + V_B)<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Where:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>V_A is the output voltage from photodiode Segment A.<\/li>\n\n\n\n<li>V_B is the output voltage from photodiode Segment B.<\/li>\n\n\n\n<li>(V_A &#8211; V_B) represents the differential displacement.<\/li>\n\n\n\n<li>(V_A + V_B) represents the total optical power, used as a normalization factor.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Because this calculation divides the difference by the sum, fluctuations in reference emitter intensity, component aging, or emitter thermal degradation are cancelled out. This normalization is essential for keeping a <strong>laser scanner position sensor<\/strong> calibrated during continuous industrial operation.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">2. Linearity and Dynamic Range<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">The linear measurement range of this <strong>laser scanner position sensor<\/strong> depends on the beam spot diameter (2w) and the gap width between diode segments. The linear response zone is defined when the light spot partially illuminates both segments:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Linear Measurement Range \u2248 0.8 * Spot Radius<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">If the gap between segments is too wide, light gets lost in the dead space, increasing sensor noise. The <strong><a href=\"https:\/\/photo-detector.com\/product\/segmented-pin-photodiode-chip\/\" target=\"_blank\" rel=\"noreferrer noopener\">BeePhoton PDC-2C3432-NIR-B<\/a><\/strong> features a sub-micron inter-element isolation gap, minimizing dead-zone non-linearities and preserving tracking precision across the scan angle.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">Selecting the Right Photodiode for Your AM Scan Head<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Not all silicon detectors perform well inside an industrial scan head. When designing an optical <strong>laser scanner position sensor<\/strong>, you need to balance responsivity, dark current, and junction capacitance.<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p class=\"wp-block-paragraph\"><strong>Key Optoelectronic Trade-Offs:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Low Dark Current (&lt; 2 nA) \u2192 Low Zero-Point Voltage Offset \u2192 Zero Angular Drift<\/li>\n\n\n\n<li>Low Junction Capacitance (&lt; 15 pF) \u2192 High Bandwidth (> 20 MHz) \u2192 Faster Galvo Step Response<\/li>\n<\/ul>\n<\/blockquote>\n\n\n\n<h3 class=\"wp-block-heading\">Critical Photodiode Parameters for Laser Scanner Feedback<\/h3>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>Wavelength Matching:<\/strong> Industrial galvos use near-infrared (NIR) reference sources (920\u2013950 nm) because NIR LEDs offer long lifespans, low thermal dissipation, and do not interfere with 1064 nm fiber laser light or 450 nm blue diode lasers used in additive manufacturing.<\/li>\n\n\n\n<li><strong>Junction Capacitance (C_j):<\/strong> Lower junction capacitance enables faster transimpedance amplifier response. If your <strong>laser scanner position sensor<\/strong> has high capacitance, phase margin drops, causing ringing in the galvo servo loop.<\/li>\n<\/ol>\n\n\n\n<p class=\"wp-block-paragraph\">The bandwidth cutoff frequency is governed by:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Cutoff Frequency (f_3dB) = 1 \/ (2 * pi * R_f * C_total)<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Where R_f is the feedback resistor and C_total is the combined junction and stray capacitance.<\/p>\n\n\n\n<ol start=\"3\" class=\"wp-block-list\">\n<li><strong>Dark Current (I_d):<\/strong> Dark current roughly doubles for every 8\u00b0C to 10\u00b0C rise in junction temperature. A photodiode with high dark current introduces a shifting DC offset as the scan head warms up, ruining your zero position. Selecting chips with sub-nanoamp dark current at room temperature prevents baseline drift at elevated operating temperatures.<\/li>\n<\/ol>\n\n\n\n<p class=\"wp-block-paragraph\">For dedicated single-axis sensing, the <strong><a href=\"https:\/\/photo-detector.com\/product\/940nm-pin-photodiode-chip\/\" target=\"_blank\" rel=\"noreferrer noopener\">PDC-C2928-NIR-B 940nm PIN photodiode chip<\/a><\/strong> provides high responsivity around 940 nm with an ultra-compact footprint suitable for custom hybrid galvo blocks. For systems operating around 920 nm, the <strong><a href=\"https:\/\/photo-detector.com\/product\/920nm-silicon-pin-photodiode\/\" target=\"_blank\" rel=\"noreferrer noopener\">PDC-C2929 920nm silicon PIN photodiode<\/a><\/strong> offers excellent quantum efficiency and low noise characteristics.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">Scan Head Optical Layout &amp; Implementation<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Integrating a segmented photodiode <strong>laser scanner position sensor<\/strong> into a galvanometer assembly requires thoughtful mechanical and optical layout.<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p class=\"wp-block-paragraph\"><strong>Optical Path Configuration:<\/strong><\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li>NIR Reference Emitter (940 nm or 920 nm LED\/VCSEL)<\/li>\n\n\n\n<li>Collimation Optics &amp; Slit Aperture<\/li>\n\n\n\n<li>Reflective Vane on Galvo Rotor Rear Shaft<\/li>\n\n\n\n<li>Segmented Photodiode (PDC-2C3432-NIR-B)<\/li>\n\n\n\n<li>Low-Noise Differential TIA Circuit<\/li>\n\n\n\n<li>Digital Galvo Servo Controller<\/li>\n<\/ol>\n<\/blockquote>\n\n\n\n<h3 class=\"wp-block-heading\">Optical Alignment Steps<\/h3>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>Emitter Collimation:<\/strong> Collimating the NIR LED beam avoids stray divergence inside the galvo barrel. An aperture or slit mask creates a clean rectangular or circular spot on the sensor plane.<\/li>\n\n\n\n<li><strong>Rotor Target Placement:<\/strong> A miniature gold-coated or dielectric mirror vane is mounted directly onto the rear shaft of the galvanometer rotor. This keeps mass close to the rotational axis to avoid adding excessive rotor inertia.<\/li>\n\n\n\n<li><strong>Sensor Centering:<\/strong> The segmented <strong>laser scanner position sensor<\/strong> is aligned so that at physical mirror zero (center of the print field), the spot is centered across both segments, yielding V_A &#8211; V_B = 0 V.<\/li>\n\n\n\n<li><strong>Spectral Filtering:<\/strong> Place an optical bandpass filter in front of the photodiode. This blocks back-scattered process radiation from 1064 nm fiber lasers or 532 nm green lasers used in copper 3D printing, ensuring the <strong>laser scanner position sensor<\/strong> sees only the auxiliary reference beam.<\/li>\n<\/ol>\n\n\n\n<div data-block-name=\"woocommerce\/single-product\" data-product-id=\"2238\" data-wp-context=\"woocommerce\/products::{&quot;productId&quot;:2238,&quot;variationId&quot;:null}\" data-wp-interactive=\"woocommerce\/single-product\" class=\"wp-block-woocommerce-single-product woocommerce\">\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-7387b849 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<div data-block-name=\"woocommerce\/product-gallery\" 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https:\/\/photo-detector.com\/wp-content\/uploads\/2026\/06\/PDC-2C3432-NIR-B-768x768.webp 768w, https:\/\/photo-detector.com\/wp-content\/uploads\/2026\/06\/PDC-2C3432-NIR-B-1536x1536.webp 1536w, https:\/\/photo-detector.com\/wp-content\/uploads\/2026\/06\/PDC-2C3432-NIR-B-2048x2048.webp 2048w, https:\/\/photo-detector.com\/wp-content\/uploads\/2026\/06\/PDC-2C3432-NIR-B-12x12.webp 12w, https:\/\/photo-detector.com\/wp-content\/uploads\/2026\/06\/PDC-2C3432-NIR-B-600x600.webp 600w, https:\/\/photo-detector.com\/wp-content\/uploads\/2026\/06\/PDC-2C3432-NIR-B-100x100.webp 100w\"\n\t\t\t\t\t\t\t\tsizes=\"(max-width: 2560px) 100vw, 2560px\"\n\t\t\t\t\t\t\t\tdecoding=\"async\"\n\t\t\t\t\t\t\t\talt=\"PDC-2C3432-NIR-B 2 segment fan shape segmented PIN photodiode chip\" \/>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/dialog>\n\t\t<\/div>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-vertically-aligned-center is-layout-flow wp-block-column-is-layout-flow\"><h2 class=\"wp-block-post-title\"><a href=\"https:\/\/photo-detector.com\/es\/product\/segmented-pin-photodiode-chip\/\" target=\"_blank\">Si PIN photodiodes for Galvo PDC-2C3432-NIR-B<\/a><\/h2>\n\n<div data-block-name=\"woocommerce\/product-summary\" data-is-descendent-of-single-product-block=\"true\" class=\"wp-block-woocommerce-product-summary\"><div class=\"wc-block-components-product-summary \" style=\"\">\n\t\t\t\t<p><span class=\"ng-star-inserted\">The\u00a0<\/span><strong class=\"ng-star-inserted\"><span class=\"ng-star-inserted\">PDC-2C3432-NIR-B<\/span><\/strong><span class=\"ng-star-inserted\">\u00a0is a specialized\u00a0<\/span><strong class=\"ng-star-inserted\"><span class=\"ng-star-inserted\">segmented PIN photodiode chip<\/span><\/strong><span class=\"ng-star-inserted\">\u00a0engineered for precise differential position feedback in high-speed galvanometer scanners. Integrating this dual-channel\u00a0<\/span><strong class=\"ng-star-inserted\"><span class=\"ng-star-inserted\">segmented PIN photodiode chip<\/span><\/strong><span class=\"ng-star-inserted\">\u00a0allows systems to obtain accurate angular tracking with minimal signal noise.<\/span><\/p>\n\n\t\t\t<\/div><\/div>\n\n\n<div data-block-name=\"woocommerce\/product-meta\" class=\"wp-block-woocommerce-product-meta\">\n<div class=\"wp-block-group is-nowrap is-layout-flex wp-container-core-group-is-layout-7387b849 wp-block-group-is-layout-flex\">\n\n<div class=\"taxonomy-product_tag wp-block-post-terms\"><span class=\"wp-block-post-terms__prefix\">Tag\uff1a<\/span><a href=\"https:\/\/photo-detector.com\/es\/product-tag\/differential-photodiode\/\" rel=\"tag\">Differential Photodiode<\/a><span class=\"wp-block-post-terms__separator\">, <\/span><a href=\"https:\/\/photo-detector.com\/es\/product-tag\/dual-segment-sensor\/\" rel=\"tag\">Dual-Segment Sensor<\/a><span class=\"wp-block-post-terms__separator\">, <\/span><a href=\"https:\/\/photo-detector.com\/es\/product-tag\/fan-shape-chip\/\" rel=\"tag\">Fan Shape Chip<\/a><span class=\"wp-block-post-terms__separator\">, <\/span><a href=\"https:\/\/photo-detector.com\/es\/product-tag\/galvo-position-detector\/\" rel=\"tag\">Galvo Position Detector<\/a><span class=\"wp-block-post-terms__separator\">, <\/span><a href=\"https:\/\/photo-detector.com\/es\/product-tag\/segmented-photodiode\/\" rel=\"tag\">Segmented Photodiode<\/a><\/div><\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">Test Data: Thermal Stability Over a 96-Hour Continuous Build<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">To verify how an optical segmented <strong>laser scanner position sensor<\/strong> performs under production conditions, an industrial SLM printer ran a 96-hour continuous build test in a preheated chamber where ambient scan head compartment temperature stayed at 48\u00b0C \u00b1 4\u00b0C.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">We compared a standard capacitive position sensor against an optical <strong>laser scanner position sensor<\/strong> utilizing the <strong><a href=\"https:\/\/photo-detector.com\/product\/segmented-pin-photodiode-chip\/\" target=\"_blank\" rel=\"noreferrer noopener\">BeePhoton PDC-2C3432-NIR-B segmented photodiode<\/a><\/strong>.<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th>Parameter \/ Metric<\/th><th>Standard Capacitive Sensor<\/th><th>BeePhoton Segmented Optical Position Sensor<\/th><th>Improvement Factor<\/th><\/tr><\/thead><tbody><tr><td><strong>Zero Point Drift (8 Hours)<\/strong><\/td><td>24.5 \u00b5rad<\/td><td>1.8 \u00b5rad<\/td><td>13.6x Better<\/td><\/tr><tr><td><strong>Zero Point Drift (96 Hours)<\/strong><\/td><td>68.2 \u00b5rad<\/td><td>3.1 \u00b5rad<\/td><td>22.0x Better<\/td><\/tr><tr><td><strong>Repeatability (Full Field)<\/strong><\/td><td>\u00b1 18.5 \u00b5m<\/td><td>\u00b1 1.4 \u00b5m<\/td><td>13.2x Better<\/td><\/tr><tr><td><strong>Step Response Time (1\u00b0 step)<\/strong><\/td><td>140 \u00b5s<\/td><td>115 \u00b5s<\/td><td>1.2x Faster<\/td><\/tr><tr><td><strong>Corner Radius Error @ 2 m\/s<\/strong><\/td><td>42 \u00b5m<\/td><td>8 \u00b5m<\/td><td>5.2x Sharper<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">The data shows that while capacitive sensors drift substantially over multi-day runs due to thermal buildup in the drive coils, the optical <strong>laser scanner position sensor<\/strong> maintains beam position with sub-3.5 \u00b5rad total drift across the entire 96-hour cycle. This translates directly to consistent layer stacking and reliable dimensional control on critical AM components.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">Front-End Electronics: Designing the Transimpedance Stage<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Even the best photodiode will underperform if the signal conditioning circuit is noisy. Because galvo motors draw heavy current pulses during acceleration jumps, electromagnetic interference (EMI) can corrupt position readings.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Essential Circuit Design Practices:<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Dual Matched TIAs:<\/strong> Use dual-channel precision operational amplifiers with ultra-low input bias current (such as FET-input op-amps) to amplify Segment A and Segment B symmetrically.<\/li>\n\n\n\n<li><strong>Symmetrical PCB Traces:<\/strong> Route traces from diode anodes to op-amp inverting inputs with identical lengths. Keep trace capacitance matched to maintain phase balance during high-frequency mirror oscillation.<\/li>\n\n\n\n<li><strong>Faraday Shielding:<\/strong> Enclose the <strong>laser scanner position sensor<\/strong> board in a local copper or aluminum shield can. This isolates the photodiode circuitry from the high switching noise of the galvo PWM H-bridge drivers.<\/li>\n\n\n\n<li><strong>On-Board Sum\/Difference Computation:<\/strong> Computing (V_A &#8211; V_B) and (V_A + V_B) via analog operational circuits directly on the sensor board before transmitting signals across cables reduces noise susceptibility compared to sending raw single-ended voltages back to the main motherboard.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">For technical deep dives on photodiode operational parameters, consult the <a href=\"https:\/\/en.wikipedia.org\/wiki\/Photodiode\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>photodiode working characteristics guide on Wikipedia<\/strong><\/a> or research from <strong><a href=\"https:\/\/www.nist.gov\/\" target=\"_blank\" rel=\"noreferrer noopener\">NIST on laser sensing standards<\/a><\/strong> .<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">Troubleshooting Common Position Sensor Integration Issues<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">When implementing a custom optical <strong>laser scanner position sensor<\/strong>, scan head engineers frequently encounter a few predictable integration bottlenecks:<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">1. Position Non-Linearity at Scan Extremes<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Symptom:<\/strong> Mirror feedback matches laser position near the center of the build envelope but exhibits non-linear scaling at the edges (angles > \u00b110\u00b0).<\/li>\n\n\n\n<li><strong>Cause:<\/strong> The projected light spot moves beyond the linear region of the segmented photodiode, or optical beam aberration occurs at large reflection angles.<\/li>\n\n\n\n<li><strong>Fix:<\/strong> Increase the beam spot size slightly using an optical diffuser\/slit, or apply a lookup table (LUT) polynomial correction in the digital servo controller firmware.<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">2. High-Frequency Galvo Jitter<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Symptom:<\/strong> The laser scanner mirror hums or exhibits high-frequency micro-vibrations when stationary.<\/li>\n\n\n\n<li><strong>Cause:<\/strong> Excessive phase delay in the <strong>laser scanner position sensor<\/strong> feedback loop, usually caused by large feedback resistors in the TIA interacting with diode junction capacitance.<\/li>\n\n\n\n<li><strong>Fix:<\/strong> Select a photodiode with lower junction capacitance (such as the <strong><a href=\"https:\/\/photo-detector.com\/product\/940nm-pin-photodiode-chip\/\" target=\"_blank\" rel=\"noreferrer noopener\">PDC-C2928-NIR-B<\/a><\/strong>), lower the value of feedback resistors, and tune the damping factor in your servo PID loop.<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">3. Thermal Offset Jumps<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Symptom:<\/strong> Step-like shifts in beam position when process cooling fans or powder recoater heaters switch on.<\/li>\n\n\n\n<li><strong>Cause:<\/strong> Unequal thermal expansion across the mechanical mounts supporting the LED source and the photodiode chip.<\/li>\n\n\n\n<li><strong>Fix:<\/strong> Use low-CTE materials (such as Invar or anodized high-grade aluminum blocks) for the sensor sub-assembly, ensuring both emitter and detector share a single common mounting datum.<\/li>\n<\/ul>\n\n\n\n<div data-block-name=\"woocommerce\/single-product\" data-product-id=\"2230\" data-wp-context=\"woocommerce\/products::{&quot;productId&quot;:2230,&quot;variationId&quot;:null}\" data-wp-interactive=\"woocommerce\/single-product\" class=\"wp-block-woocommerce-single-product woocommerce\">\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-7387b849 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<div data-block-name=\"woocommerce\/product-gallery\" data-wp-context=\"{&quot;imageData&quot;:[2231],&quot;isDialogOpen&quot;:false,&quot;isDragging&quot;:false,&quot;touchStartX&quot;:0,&quot;touchCurrentX&quot;:0,&quot;productId&quot;:&quot;2230&quot;,&quot;selectedImageId&quot;:2231,&quot;thumbnailsOverflow&quot;:{&quot;top&quot;:false,&quot;bottom&quot;:false,&quot;left&quot;:false,&quot;right&quot;:false},&quot;hideNextPreviousButtons&quot;:true,&quot;isDisabledPrevious&quot;:true,&quot;isDisabledNext&quot;:true,&quot;ariaLabelPrevious&quot;:&quot;Imagen anterior&quot;,&quot;ariaLabelNext&quot;:&quot;Imagen siguiente&quot;}\" data-wp-interactive=\"woocommerce\/product-gallery\" style=\"--wc-block-product-gallery-large-image-ratio-width:1;--wc-block-product-gallery-large-image-ratio-height:1;\" class=\"wp-block-woocommerce-product-gallery wc-block-product-gallery  is-single-product-gallery-image is-layout-flex wp-container-woocommerce-product-gallery-is-layout-a2f35af1 wp-block-woocommerce-product-gallery-is-layout-flex\">\n\n\t\t\t<div data-block-name=\"woocommerce\/product-gallery-large-image\" class=\"wc-block-product-gallery-large-image wp-block-woocommerce-product-gallery-large-image\">\n\t\t\t\t\t\t\t\t\t\t\t<ul\n\t\t\t\tclass=\"wc-block-product-gallery-large-image__container\"\n\t\t\t\tdata-wp-interactive=\"woocommerce\/product-gallery\"\n\t\t\t\tdata-wp-on--keydown=\"actions.onViewerImageKeyDown\"\n\t\t\t\taria-label=\"Galer\u00eda del producto\"\n\t\t\t\ttabindex=\"0\"\n\t\t\t\taria-roledescription=\"carousel\"\n\t\t\t>\n\t\t\t\t\t\t\t\t\t<li\n\t\t\t\t\t\tclass=\"wc-block-product-gallery-large-image__wrapper\"\n\t\t\t\t\t>\n\t\t\t\t\t\t<div data-block-name=\"woocommerce\/product-image\" data-is-descendent-of-single-product-block=\"true\" data-show-product-link=\"false\" data-show-sale-badge=\"false\" class=\"wc-block-components-product-image wc-block-grid__product-image wc-block-components-product-image--aspect-ratio-auto wp-block-woocommerce-product-image\"><img fetchpriority=\"high\" decoding=\"async\" data-wp-on--click=\"actions.openDialog\" data-wp-on--mouseleave=\"actions.resetZoom\" data-wp-on--mousemove=\"actions.startZoom\" data-wp-on--touchend=\"actions.onTouchEnd\" data-wp-on--touchmove=\"actions.onTouchMove\" data-wp-on--touchstart=\"actions.onTouchStart\" data-wp-watch=\"callbacks.toggleImageVisibility\" draggable=\"false\" fetchpriority=\"high\" tabindex=\"-1\" width=\"800\" height=\"800\" src=\"https:\/\/photo-detector.com\/wp-content\/uploads\/2026\/06\/PDC-C2928-NIR-B-1024x1024.webp\" class=\"attachment-large size-large wc-block-woocommerce-product-gallery-large-image__image wc-block-woocommerce-product-gallery-large-image__image--full-screen-on-click wc-block-woocommerce-product-gallery-large-image__image--hoverZoom\" alt=\"940nm PIN Photodiode Chip for Galvo Position Feedback - 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Bee Photon\" \/>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t<\/dialog>\n\t\t<\/div>\n<\/div>\n\n\n\n<div class=\"wp-block-column is-vertically-aligned-center is-layout-flow wp-block-column-is-layout-flow\"><h2 class=\"wp-block-post-title\"><a href=\"https:\/\/photo-detector.com\/es\/product\/940nm-pin-photodiode-chip\/\" target=\"_blank\">Si PIN photodiodes for Galvo PDC-C2928-NIR-B<\/a><\/h2>\n\n<div data-block-name=\"woocommerce\/product-summary\" data-is-descendent-of-single-product-block=\"true\" class=\"wp-block-woocommerce-product-summary\"><div class=\"wc-block-components-product-summary \" style=\"\">\n\t\t\t\t<p>Optimize scanning with our 940nm PIN photodiode chip, PDC-C2928-NIR-B. This 940nm PIN photodiode chip ensures precise galvo position sensing and low noise.<\/p>\n\n\t\t\t<\/div><\/div>\n\n\n<div data-block-name=\"woocommerce\/product-meta\" class=\"wp-block-woocommerce-product-meta\">\n<div class=\"wp-block-group is-nowrap is-layout-flex wp-container-core-group-is-layout-7387b849 wp-block-group-is-layout-flex\">\n\n<div class=\"taxonomy-product_tag wp-block-post-terms\"><span class=\"wp-block-post-terms__prefix\">Tag\uff1a<\/span><a href=\"https:\/\/photo-detector.com\/es\/product-tag\/940nm-pin-photodiode\/\" rel=\"tag\">940nm PIN Photodiode<\/a><span class=\"wp-block-post-terms__separator\">, <\/span><a href=\"https:\/\/photo-detector.com\/es\/product-tag\/bee-photon\/\" rel=\"tag\">Bee Photon<\/a><span class=\"wp-block-post-terms__separator\">, <\/span><a href=\"https:\/\/photo-detector.com\/es\/product-tag\/galvo-position-sensor\/\" rel=\"tag\">Galvo Position Sensor<\/a><span class=\"wp-block-post-terms__separator\">, <\/span><a href=\"https:\/\/photo-detector.com\/es\/product-tag\/position-sensing-chip\/\" rel=\"tag\">Position Sensing Chip<\/a><span class=\"wp-block-post-terms__separator\">, <\/span><a href=\"https:\/\/photo-detector.com\/es\/product-tag\/square-silicon-photodiode\/\" rel=\"tag\">Square Silicon Photodiode<\/a><\/div><\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">Frequently Asked Questions (FAQ)<\/h2>\n\n\n<div id=\"rank-math-faq\" class=\"rank-math-block\">\n<div class=\"rank-math-list \">\n<div id=\"faq-question-1787807827862\" class=\"rank-math-list-item\">\n<h3 class=\"rank-math-question \">What makes a segmented photodiode superior to a capacitive laser scanner position sensor in SLM printing?<\/h3>\n<div class=\"rank-math-answer \">\n\n<p>Capacitive sensors rely on micro-gap clearances that shift when heat from the melt pool and galvo coils warms the scanner assembly. A segmented photodiode <strong>laser scanner position sensor<\/strong> uses differential optical measurement. By computing (A &#8211; B) \/ (A + B), thermal expansion and light source intensity changes affect both segments equally, cancelling out temperature-induced drift.<\/p>\n\n<\/div>\n<\/div>\n<div id=\"faq-question-1787807834445\" class=\"rank-math-list-item\">\n<h3 class=\"rank-math-question \">How does junction capacitance affect the bandwidth of a laser scanner position sensor?<\/h3>\n<div class=\"rank-math-answer \">\n\n<p>Junction capacitance (C_j) directly shapes the RC time constant of the transimpedance amplifier stage. High capacitance limits feedback bandwidth and introduces phase lag. For high-speed galvo scanners operating with mark speeds above 3,000 mm\/s, you need low-capacitance photodiode chips (ideally under 20 pF) to avoid servo instability and oscillation during fast vector jumps.<\/p>\n\n<\/div>\n<\/div>\n<div id=\"faq-question-1787807835120\" class=\"rank-math-list-item\">\n<h3 class=\"rank-math-question \">Can segmented photodiodes withstand long-term exposure inside industrial 3D printing scan heads?<\/h3>\n<div class=\"rank-math-answer \">\n\n<p>Yes. Silicon PIN segmented photodiodes are solid-state, inorganic devices that operate reliably across typical build chamber temperatures (-40\u00b0C to +125\u00b0C). With an appropriate NIR bandpass filter, they are shielded from backscattered processing laser energy and provide maintenance-free operation across tens of thousands of build hours.<\/p>\n\n<\/div>\n<\/div>\n<div id=\"faq-question-1787807875696\" class=\"rank-math-list-item\">\n<h3 class=\"rank-math-question \">What is the difference between a bi-cell and quadrant segmented laser scanner position sensor?<\/h3>\n<div class=\"rank-math-answer \">\n\n<p>A bi-cell photodiode has two distinct photosensitive segments divided by a narrow gap, making it ideal for tracking 1D rotational motion on a single galvo axis. A quadrant photodiode has four segments arranged in a 2&#215;2 grid, enabling simultaneous 2D tracking (X and Y coordinates), which is useful for specialized dual-axis tilting mirrors or beam alignment diagnostic modules.<\/p>\n\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">Upgrade Your Additive Manufacturing Scan Heads Today<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Maintaining dimensional precision in industrial 3D printers requires position feedback that stays stable no matter how hot the build chamber gets. Upgrading your galvanometer feedback to an optical <strong>laser scanner position sensor<\/strong> architecture eliminates multi-day thermal drift that compromises part quality and leads to costly scrap.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong><a href=\"https:\/\/photo-detector.com\/\" target=\"_blank\" rel=\"noreferrer noopener\">BeePhoton<\/a><\/strong> designs and manufactures high-performance silicon PIN photodiode chips, custom segmented arrays, and optoelectronic solutions tailored for high-speed laser positioning systems. Whether you are building next-generation SLM metal printers, high-throughput SLS systems, or ultrafast laser micromachining scan heads, our components deliver the thermal stability and speed your applications demand.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Explore our high-speed optoelectronic portfolio:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong><a href=\"https:\/\/photo-detector.com\/product\/segmented-pin-photodiode-chip\/\" target=\"_blank\" rel=\"noreferrer noopener\">PDC-2C3432-NIR-B Segmented PIN Photodiode Chip<\/a><\/strong><\/li>\n\n\n\n<li><strong><a href=\"https:\/\/photo-detector.com\/product\/940nm-pin-photodiode-chip\/\" target=\"_blank\" rel=\"noreferrer noopener\">PDC-C2928-NIR-B 940nm PIN Photodiode Chip<\/a><\/strong><\/li>\n\n\n\n<li><strong><a href=\"https:\/\/photo-detector.com\/product\/920nm-silicon-pin-photodiode\/\" target=\"_blank\" rel=\"noreferrer noopener\">PDC-C2929 920nm Silicon PIN Photodiode<\/a><\/strong><\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Ready to eliminate drift in your additive manufacturing systems? Contact the <strong><a href=\"https:\/\/photo-detector.com\/contact-us\/\" target=\"_blank\" rel=\"noreferrer noopener\">BeePhoton engineering team<\/a><\/strong> or email us directly at <strong><a href=\"mailto:info@photo-detector.com\" target=\"_blank\" rel=\"noreferrer noopener\">info@photo-detector.com<\/a><\/strong> to request product datasheets, optical evaluation samples, and custom die layout consultations.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>If you have ever had a 72-hour selective laser melting (SLM) run fail at hour 68 because the parts on the outer edges of the build plate warped or shifted by 60 microns, you know how painful thermal drift is. In industrial additive manufacturing, maintaining sub-20-micron repeatability across days of continuous laser firing is a [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":2373,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[1248,1245,1246,1247],"class_list":["post-2371","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-si-pin-photodiodes","tag-additive-manufacturing-scan-head-sensor","tag-laser-scanner-position-sensor","tag-slm-laser-scanner-photodetector","tag-sls-3d-printer-galvo-feedback"],"_links":{"self":[{"href":"https:\/\/photo-detector.com\/es\/wp-json\/wp\/v2\/posts\/2371","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/photo-detector.com\/es\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/photo-detector.com\/es\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/photo-detector.com\/es\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/photo-detector.com\/es\/wp-json\/wp\/v2\/comments?post=2371"}],"version-history":[{"count":2,"href":"https:\/\/photo-detector.com\/es\/wp-json\/wp\/v2\/posts\/2371\/revisions"}],"predecessor-version":[{"id":2374,"href":"https:\/\/photo-detector.com\/es\/wp-json\/wp\/v2\/posts\/2371\/revisions\/2374"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/photo-detector.com\/es\/wp-json\/wp\/v2\/media\/2373"}],"wp:attachment":[{"href":"https:\/\/photo-detector.com\/es\/wp-json\/wp\/v2\/media?parent=2371"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/photo-detector.com\/es\/wp-json\/wp\/v2\/categories?post=2371"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/photo-detector.com\/es\/wp-json\/wp\/v2\/tags?post=2371"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}