| | | JENCOLOUR® True Colour Sensor ICs are specifically designed for sensitivity to yield a significantly improved performance where colour deviations have to be resolved. Each sensor IC consists of a PIN photodiode with sensitivity optimised for the visible wavelength range, and a directly mounted interference filter. Of greater blue-sensitivity, these sensors also provide a general improvement in practical operating values. The interference filter represents on-chip-microstructured filter layers. These feature high transmission in the bandpass range and resistance to aging, mechanical impacts and thermal influences. Interference filters which are directly deposited onto a silicon waver have already recommended themselves in many applications. How good a result can be achieved by colour measurement essentially depends on the type and quality of the filter function. | | The new generation of JENCOLOUR® True Colour Sensors implements the tri-stimulus value function (under DIN 5033, part 2) in a way that allows colours to be determined according to the three range procedure -measurement with spectral properties -as defined in part 6 of DIN 5033. It facilitates applications for "sufficiently accurate detection" of emitting, remitting, or transmitting samples. Such applications include, for example, LED testing and sorting, monitor calibrating, or simple, compact and low-cost modules for colour measurement. The spectral sensitivity distribution of each interference filter cell is obtained as a functional diagram of the spectral sensitivity of the filter's base material versus its transmittance, with the standard distribution function representing the sensor's actual sensitivity. The output currents of the colour sensor ICs are a function of the spectral composition of incident light, | | |
| | | weighted with the function of the filter which is mounted to the photodiode. A special factor is defined for gain matching of, and normalisation of the values measured in each channel, in order to fulfil Luther's condition. The resulting absolute standard spectral coefficients for XYZ are available for further mathematical conversion into a randomly selectable colour space. | | |