JB COS is an unique cosine receptor specifically designed for accurate measurement of solar irradiance.  With its high transmittance and innovative design enable to reduce significantly the light loss and to provide measurmente with an almost perfect cosine response.



The JB COS Cosine receptor is designed for outdoors used mostly. Usually it is coupled with JB devices (FloX and RoX system) for accurate measurement of solar Irradiance in the full hemisphere. Its thread is made to be used in conjunction with an SMA-terminated fiber optic.

Due to its innovative design JB COS is characterized by an high light throughput and an excellent cosine response. Particularly suitable for measurements in the VIS NIR domain (400-1000 nm).  NIR diffusers are available upon request.



Cosine error

< 10% at 80 degree

Spectral range

400 nm - 1000 nm

Dimension - diameter

10 mm

Dimension - height

30 mm


How to calibrate the optical channel equipped by JB COS

In order to perform a radiometric calibration of the channel with JB COS connected you would need an integrating sphere, having a diameter at least of 1 cm. Eventual cross calibration with other channel or versus an additional spectrometer is also optional.

How long the calibration will last in field installation?

The answer is, as in most of the cases: it depends. In dust environment (e.g. agricultural fields, towns) it is recommended a frequent maintenance by cleaning the optics with common optical cleaners. In air cleaned environments a periodical cleaning (e.g. 6 months) is usually fine.

Can I remove JB COS and fix it back without loosing calibration?

YES. We found out that removing the receptor and placing it back it has an impact, but is really low (up to 2%).


Iterative design of a high light throughput cosine receptor fore optic for unattended proximal remote sensing. Journal of Applied Remote Sensing. 2022.

Andreas Burkart, Mitchell Kennedy, Paul Näthe, Tommaso Julitta


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