Insturment Systems has released the TOP 200 telescopic optical probe. In combination with a spectrometer, the probe permits precise measurements of radiance and luminance, as well as chromaticity of displays, panel graphics and other light sources. The core of the innovations compared with the previous model is a Pritchard style optical design with integrated view-finder camera and an aperture mirror angled at just 15°. This set-up provides a perfectly round and sharp measuring spot for maximum accuracy. The internal camera allows the field of view to be visualised on a PC, thereby facilitating both the exact positioning of the probe and the focusing of the measuring spot.
A series of easily interchangeable lenses and software controlled apertures accommodates a large range of distances and measuring spot sizes. The smallest measuring spot can be achieved with the high resolution objective lens, HRL-90, 75μm in diameter.
The light radiation is guided to the spectrometer along a multi-modal fibre. The patented mode mixer from Instrument Systems delivers uniform light transmission in the fibre, and thereby facilitates reproducible measuring results, even if the position of the fibre is changed. The measuring error is below one per cent, compared with an error of up to 20 per cent when no mode mixing is employed.