A camera sensor (CMOS or CCD) is a critical component within a 3D Optical Sensor Head responsible for capturing light from the target scene. It converts incoming photons into electrical charge, which is then processed to generate digital image data. This data forms the fundamental input for subsequent 3D reconstruction algorithms, such as structured light analysis or stereo vision, enabling the measurement of depth, shape, and surface characteristics of objects. The sensor typically consists of an array of photodiodes fabricated on a silicon substrate, along with supporting circuitry for readout and amplification. A protective glass cover shields the sensitive area from environmental contaminants. Key parameters include resolution (1–50 MP), optical format (1/4–1 inch), pixel size (1.0–10 µm), frame rate (30–240 fps), dynamic range (60–100 dB), signal-to-noise ratio (40–60 dB), supply voltage (1.8–3.3 V DC), power consumption (50–500 mW), operating temperature (-30–70 °C), storage temperature (-40–85 °C), interface options (MIPI, LVDS, parallel), package types (CSP, COB, LCC), and weight (0.5–5 g). These values are typical ranges and must be verified for the specific model and application. The sensor's performance directly influences the accuracy and reliability of 3D measurements. When selecting a sensor, consider factors such as required resolution, speed, light sensitivity, and environmental conditions. Interface compatibility with the processing unit is essential. Verification of model-specific specifications and compliance with applicable standards should be confirmed with the legal manufacturer or supplier. Maintenance signals include image artifacts, dead pixels, or reduced sensitivity, which may indicate sensor degradation or contamination. Failure boundaries are defined by the sensor's operating limits; exceeding them can cause permanent damage. Proper handling and adherence to specified conditions are necessary for reliable operation.
Light from the scene passes through the sensor's lens and micro-lens array, striking an array of photodiodes (pixels). In a CCD (Charge-Coupled Device) sensor, accumulated charge is transferred sequentially to a readout amplifier. In a CMOS (Complementary Metal-Oxide-Semiconductor) sensor, each pixel typically has its own amplifier, allowing for faster and more flexible readout. The electrical signal is then digitized by an analog-to-digital converter (ADC) to produce a digital image.
