The model 263 miniature Photometric sensors are designed with spectral responsivity that matches the human visual system, incorporating a silicon detector combined with a spectrally matched photometric filter.  An integrated cosine filter significantly reduces directional sensitivity for ease of use.

Our wide range of optical power meters, photometric and radiometric sensors is complemented by ISO/IEC 17025 accreditation by NVLAP (NVLAP lab code 200823-0), resulting in unmatched performance and custom configuration as required.

  • Illuminance Measurements (lux)
  • Luminous Intensity Measurements (cd)
  • Luminous Flux Measurements (lm) when used with model 2575 mini-sphere

 Key Specifications                                                         Part No. U23-01-180

 CIE V (λ) Function

 f1’  ≤ 3% (standard)

 f1′  ≤ 1% (special order)

 Detector Information

Silicon     0.34 cm2 active area

 Rise Time

1 µ sec

 Dynamic Range(1)

5 x 10-1 to 5 x 105 lux

 Typical Response(1)

7.3 x 10-10 A/lux


ISO 17025, NIST Traceable


2 meter, included

 Compatible with the UDT Handheld and Benchtop series Optical  Meters and Integrating Spheres.

 (1) Stand alone with cosine receptor. Value may differ when used with integrating sphere, other accessories, or with cosine receptor removed.


UDT Model 263 Photometric Sensor