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Position Sensitive Phototransistors

Phototransistors have a sensitivity to light that is magnitudes higher than conventional PSDs.

Highly sensitive phototransistors

While conventional PSDs (position sensitive detectors) always depended on photodiodes and had a sensitivity that did suffice for all applications, the new ES PSD series from SiTek is based on phototransistors. With phototransistors the light sensitivity has increased significantly. These sensors are therefore particularly well-suited for applications in which only a very small laser intensity is available or for eye-safe measurement systems.


2 Types:
The 1L10ES has an active surface area of 10 x 2 mm² and comes in a 14-pin DIL housing with protective glass. The position non-linearity is typically 0.05%, the noise typically 0.4 pA/(Hz)1/2, the sensitivity 3 A/W, and the rise time typically 2 µs.

The 2L10ES has an active area of 10 x 10mm². The position non-linearity is not more than 0.8%, the noise 1.3 pA/(Hz)1/2, the sensitivity 3 A/W, and the rise time is typically 4 µs. It comes in a 4-pin, 25 x 25 mm² large ceramic housing with protective glass.

Samples and further versions
Samples of both types are available. Currently in development, versions of the ES PSD sensors for the visible wavelength range, the near infrared range, and the UV range with even higher sensitivity will be available soon. They can be customized according to demands similar in fashion to the standard PSDs from SiTek.


Beyond Borders

SEEPOS - PSD Signal Processing System SEEPOS - PSD Signal Processing System
Preamplifiers for PSDs

Amplifiers for PSDs, Differential Diodes, and Quadrant Diodes

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