Photon Counting Detectors


Cooled Single Photon Detector Array

  • Peltier-cooled array detector with 23 densely packed single photon avalanche diodes
  • Large effective fill factor
  • High photon detection efficiency
  • Low jitter
  • Low dark count rates

The PDA-23 is a detector assembly for single photon detection over a wide spectral range from 400 nm to 850 nm and beyond, developed in collaboration with Pi Imaging. It consists of an array of 23 single photon avalanche detectors (SPAD) with high native fill factor and microlenses (effective fill factor > 80%), high photon detection and low timing jitter.

A compact SPAD microarray chip with 23 pixelsOptimization for low dark count applications

The detector array consists of SPADs with low dark count rates of typ. 100 cps, with typically only 1 hot pixel with > 1 kcps. In the PDA-23 these dark count rates are further reduced via an integrated Peltier-cooler.

Versatile mounting options

The PDA-23 detector has a C mount in front of the sensor and mounts for optical tables for easier integration into optical set-ups. Customization for other mounting requirements is possible.

Available as add-on for MultiHarp 160 event timer

The PDA-23 is available as a detector add-on for the MultiHarp 160. It has a break-out adaptor box with 23 SMA output connectors included, which provide the output signals from each individual SPAD of the array.

Specifications (preliminary)

Active Area 100 µm x 110 µm
Native fill factor 23.5 %
Effective fill factor with microlenses > 80%
Photon detection efficiency (PDE) Typ. peak PDE 55% at 520 nm 
PDE typically above 35% for wavelengths from 440 to 660 nm
Timing jitter  < 120 ps FWHM for wavelengths between 510 and 785 nm
Dark count rates Typ. 100 cps for most pixels,
Typ. 1 hot pixel with around > 1 kcps
Peltier-cooling for even less dark counts

The following documents are available for download: