Position sensitive detectors. Spatially-resolved photodiodes measure the position of a light spot. The bandwidth and resolution of so-called position sensitive detectors (PSDs) are unmatched.
The four-quadrant diode JQA5 covers a spectral range from 205 to 355 nm.
The four-quadrant photodiode JQA5 is a monolithic component for high resolution position measurements and tracking applications and is available for the range 205 nm - 255 nm.
The active material is silicon carbide, which makes the diode "solar blind". The total diameter of the active area is 2.525 mm, and the surface area of each single quadrant is 1.25 mm². The distance between the quadrants is 32 µm, which, compared to the discontinued previous model (i.e., the JQC4) has been reduced by a factor of 5.
The typical sensitivity is 0.14 A/W in the important spectral range around the 254 nm line of mercury steam lamps and around the 248 nm line of the excimer laser.