InfiRay Finder FH25R product image

InfiRay Finder FH25R

The FINDER FH25R is a thermal monocular made by InfiRay and is part of the Finder series.


The Finder FH25R spots a clear 25mm objective lens collecting thermal radiation. The default field of view on this thermal monocular measures 17.5 by 14 degrees. It has a 6 times digital zoom to enlarge (parts of) the image. The exit pupil diameter measures 20mm.

Behind the lens of the Finder FH25R you can find the (uncooled, 12 micrometer) 640 x 512 pixel microbolometer refreshing the image at 50Hz.

The measurements of this thermal monocular read 70 x 52 x 130mm (l/w/h) and the scale reads 320 grams. It's protected against dust, shocks and water (splashes).

The Finder FH25R can be utilized in surveillance, hunting trips, law enforcement (police, border patrol etc.) and SAR (Search and Rescue) operations.


  • 12 µm pixel pitch
  • Long Range Detection
  • 50Hz realtime video
  • Laser Rangefinder (LRF)
  • Record photo & video
  • WiFi connectivity
  • Accelerometer and E-Compass


Lens25 mm
Diopter adjustment-4 +5
Exit pupil diameter20 mm
Optical zoom1.5 x
Digital zoom6 x
FOV (h/v)17.5 ° / 14 °
Thermal typeUncooled
Sensor resolution (h/v)640 pixels / 512 pixels
Pixel pitch12 µm
Display resolution (h/v)1280 pixels / 960 pixels
Refresh rate50 Hz
Output screen colorFull color
Additional detailsThis version includes a LRF
Dimensions (l/w/h)70 mm / 52 mm / 130 mm
Weight320 g
Number of batteries1
Battery life6 hours
Law enforcement
Search & rescue
Fire fighting

DRI Ranges

DRI stands for Detection, Recognition and Identification and is based on the widely used Johnson's criteria.

  • Detection Detect if an object is present
  • Recognition See what type of object it is (i.e. person, vehicle, airplane)
  • Identification For example see if someone is a friend or foe
Detection Recognition Identification
Rabbit 375 meters 93 meters 46 meters
Person 1319 meters 329 meters 164 meters
Vehicle 3194 meters 798 meters 399 meters

Please note that these values are calculated, always consult the manufacturer for official range numbers.


InfiRay Finder Series
InfiRay Finder Series
InfiRay Finder Series
InfiRay Finder Series
InfiRay Finder Series

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