VIS Spectrometer, Back-thinned CCD from 360nm-830nm

The CAS 120 is ideal for all measurement applications of LEDs, OLEDs and solid-state lighting products. Firstly, the comprehensive range of accessories transforms the setup of the spectrometer into a universal lab workstation. Secondly, the robust design, the short measuring times and attractive pricing make the CAS 120 ideal for use in cost sensitive production environments. The wafer with processed LED chips provides the opportunity to determine the properties of the future LED for the first time. In particular, this is crucially important when manufacturing white LEDs where tight production tolerances and a high yield for the final white LEDs can only be guaranteed by precise testing for the optical and electrical parameters of the blue LED chips used.

In addition, these probes can be operated under a microscope and permit fast configuration of the wafer and continuous positional control during testing. The probe’s high light throughput also facilitates very short measuring times even with low power LED chips. Moreover, the CAS 120 is equipped with a reliable, screw-fit USB interface and a separate TTL trigger I/O interface. The hardware trigger is necessary to enable precise timing and synchronization with other instruments like current sources. Minimizing synchronization errors and delays is especially critical for wafer probing and LED sorting. Trigger cables are available for direct connection of standard current sources to the CAS 120.

Review of Key specifications

A very high level of accuracy for the test results is always guaranteed even with the factory calibration of the spectrometer. This is because the CAS 120 has ISO 17025 accreditation from test laboratories operated by Instrument Systems. This fidelity is also translated by a comprehensive analytic and reporting tools which include, a luminous flux [lm] or luminous intensity [cd], color coordinates (x,y,z), color temperature [K], color rendering index (CRI), dominant centroid and peak wavelength [nm], as well as peak width at half-height FWHM [nm].

Moreover, to guarantee maximum optical precision with exceptionally good straylight rejection and a high level of optical precision, the optical setup is integrated with Czerny-Turner spectrograph and a density filter wheel and dark current shutter. Accordingly, an optical concentrator as well as a CCD area sensor with 2048 x 14 pixels, enhances the sensitivity of the spectrometer to values which are comparable with larger, more expensive detectors. Indeed, the low number of pixels in the sensor combined with the fast A/D converter results in particularly short measuring times of only 4 ms. As such, you can obtain a significantly better signal sensitivity in the short-wave spectral range (blue response) than in conventional front-illuminated CCDs which are used in low-cost spectrometers.