Photodiodes serve laser alignment, position sensing
Stephen LawElectronics Optoelectronics LASER optoelectronics photodiodes
InGaAs quadrant and array photodiodes serve laser alignment and position sensing applications. Devices are segmented photodiode position sensing detectors (PSD, AKA position sensing diodes) with four planar diffused photodiode elements, which are monolithic or on the same silicon or InGaAs chip. Quad photodiodes have low dark current, high resolution or precision, high accuracy, high response with low noise (high S/N ratio), wide spectral ranges, improved frequency bandwidth, enhanced dynamic range, minimal element spacing, low operating voltages, high shunt resistance and large active areas. InGaAs quadrant photodiodes and photodiode arrays have a wavelength sensitivity range from 600nm to 2600nm (600nm to 1700nm for the 1.7µm InGaAs PDs and 800nnm to 2600nm for the 2.6µm InGaAs PDs).