The first telecentric SWIR lens

22. August 2018

Affordable InGaAs sensors with a spectral sensitivity between 900 and 1700 nm and increasing resolution establish growing application fields (e.g. food and pharmaceutical industries) and became an additional leading force in machine vision industries.

As a specialist in telecentric optics for machine vision Sill Optics offers the first bi-telecentric lens for SWIR waveband. According to market demands, the lens is suitable for hyperspectral imaging with a wide wavelength range as well as for application with bandpass filter.

The bi-telecentric lens (part. nr. S5LPJ6835) has a magnification of 0.33 for a maxi-mum field of view of Ø48mm. The lens design is optimized for NA 0.03, that equals a F# of 5.5. With reservations regarding vignetting and maximum resolution, imaging with F# 2.0 is possible for applications with high demand in light intensity. The remaining object-sided telecentric error is less than 0.5°, the distortion is less than 0.5%.

Equivalently, we offer an entocentric SWIR lens with a focal length of 50mm (part no. S5LPJ6805). This lens has been developed for a maximum sensor size of 17.6mm (1.1’’ sensor) and a minimum F# of 1.8. It is available with C-Mount or M42 thread. The working distance can be adjusted between 400mm and infinity. Stop size and focus are mechanically adjustable and can be fixed by a locking screw. The distortion varies between <0.5% (infinite working distance) and <1.5% (working distance 400mm).

The sensor-sided telecentricity of both lenses enables the combination with spectrometers or with prism based multi-sensor cameras.

A telecentric lens with magnification 0.5 and an entocentric lens with focal length 75mm will be available soon. Both lenses are sensor-sided telecentric and specified for a sensor diagonal of 24mm.