PDP90A In Stock

The ThorLabs PDP90A is a highly advanced 2D lateral effect position-sensing detector (PSD) designed to provide precise X and Y-axis positional information. The sensor has been specifically designed to work seamlessly with the KPA101 K-Cube Auto-Aligner, making it ideal for general alignment purposes and precise position measurements. The PDP90A is highly versatile and can be utilized for measuring beam movement, distance traveled, or as feedback for alignment systems.

One of the key features of the PDP90A is its large detection surface, which can accommodate a beam diameter of less than 9 mm. Additionally, the sensor has an extremely low noise figure of less than 2 mVpp (less than 300 µVrms), which corresponds to a detection error of just 0.750 μmrms. Despite its powerful performance, the PDP90A boasts a compact footprint of just 2.00" x 1.20" x 0.65". The PDP90A can accurately measure displacement, making it an ideal tool for systems that require precise alignment, such as steering mirrors, microscopy systems, and fiber launch systems.

The PDP90A uses photo-generated electrons as an indicator to measure position, unlike other sensors which rely on surface intensity distributions. This process makes the detector capable of providing continuous position sensing. This innovative approach allows the sensor to provide highly accurate readings and ensure that the systems it's used for remain aligned to the required specifications.

The PDP90A is a light dependent variable resistor that can sense and track position in both the X and Y axes. It uses photocurrent to detect changes from the four electrodes when exposed to incident light. The two types of lateral effect sensors that are available are tetra-lateral and duo-later, both of which have their own unique advantages and disadvantages. The PDP90A uses a variation of the tetra-lateral-type sensor commonly referred to as a "pin cushion" position-sensing device. The arrangement of the anodes to the sensor’s four corners gives fairly accurate linearity results, at a much lesser cost than duo lateral sensors.

The active area of the PDP90A is 9x9 mm at the waist of the pincushion, and at the outermost regions, the area goes to 10mm. This means that calculations are performed from the widest part of the sensor. The PDP90A supports spot sizes up to 9 mm in diameter, but a spot between Ø0.2 mm and Ø7 mm is recommended for optimal performance.