CAS 140CT - The Standard for Array Spectrometers

The CAS 140CT, already in its 3rd generation, is the most successful array spectrometer from Instrument Systems worldwide. These instruments combine high accuracy with an opto-mechanically robust design and a simple operation. The range of applications is thus correspondingly wide - from 24 hour, round-the-clock operation in manufacturing to use as a reference instrument in calibration laboratories.


Centerpiece of the CAS 140CT is the newly developed Crossed-Czerny-Turner spectrograph incorporating a high-end, back-Illuminated CCD detector. The spectrometer design thus effectively reduces stray light, resulting in significantly improved dynamic range and measurement accuracy.

The CAS 140CT is the only array spectrometer to include an optical density filter wheel, extending the measurable intensity range over 4 orders of magnitude. Measurements for both very weak and very strong light sources can thus be acquired fully automatically.


  • various models from 200 to 2150 nm
  • high-end, cooled, back-Illuminated CCD detector for highest sensitivity and signal stability
  • wide intensity measurement range via integrated optical density filter wheel
  • integrated shutter for dark current measurements
  • acquisition times in the millisecond range
  • optionally USB or PCI interface
  • software solutions for laboratory and manufacturing applications


  • system solutions for testing LEDs, displays und flash lamps
  • spectroradiometry in the UV-VIS-NIR range
  • universal spectrometer for laboratory applications
  • industrial quality control in the production line

Ordering information:  

Model      Spectral range [nm] Number of pixelsSpectral
[nm] *)
back-illuminated CCD detector
CAS140CT-151360 - 830 1024 x 128 2.2 0.5
CAS140CT-152200 - 8001024 x 128 2.70.6
CAS140CT-153380 - 10401024 x 128 3.00.65
CAS140CT-154220 - 10201024 x 128 3.70.8
CAS140CT-155750 - 10501024 x 128 2.00.3
CAS140CT-156300 - 11001024 x 128 3.70.8
InGaAs or extended InGaAs detector
CAS140CT-171780 - 165051292.1
CAS140CT-1751500 - 2150256153

*) for standard 100µm slit, for 50µm slit the given values should be roughly halved

Optical design of the

The Crossed-Czerny-Turner spectrograph is housed in a mechanically robust block. The incident light is first collimated by a concave mirror and guided on to the diffraction grating, where it is spatially split into its different spectral components. A second concave mirror focuses the various spectral components of the light onto different columns of the CCD detector, thus capturing the light's spectrum in a single acquisition.