Multi-point calibration method for imaging light and color measurement device
View Patent ↗A multi-point calibration method is provided for an imaging light and color measurement device. A light emitting surface with a plurality of light emitting areas is provided. The luminance or color of each light emitting area of the light emitting surface at a specific angle is measured using a spot measurement instrument. By aligning the spot measurement instrument with one of the light emitting areas at a time, the luminance or color of the light emitting areas of the light emitting surface is measured. A measurement of the light emitting surface is made with the imaging light and color measurement device. A matrix of correction factors is calculated to correct the areas as measured by the imaging light and color measurement device to be equivalent to those measured by the spot photometer. While a display device is measured by the imaging light and color measurement device, the measured luminance or color values thereof are corrected by the screen gain correction matrix.
1. A multi-point calibration method for an imaging light and color measurement system, comprising:
aligning a spot measurement instrument with one of a plurality of light emitting areas of a light emitting surface at a specific angle to the light emitting surface and measuring the luminance or color value thereof;
moving the spot measurement instrument to align with align with another light emitting area of the light emitting surface and the luminance or color values thereof until all the light emitting areas of interest on the light emitting surface are measured;
measuring the luminance or color values of the light emitting surface using the imaging light and color measurement system; and
correcting the luminance or color values measured using the imaging light and color measurement system by the luminance or color values measured from the light emitting areas.
2. The multi-point calibration method according to claim 1 , wherein the light emitting surface is a display device.
3. A multi-point calibration method for an imaging light and color measurement system, which comprises a plurality of detectors applicable to image all light emitted from a plurality of detectors applicable to image all light emitted from a plurality of light emitting areas of a light emitting surface at once, the method comprising:
inputting parameters of the light emitting surface and test set-up to be measured to a software, so as to retrieve a corresponding screen gain correction matrix, wherein the software stores a database of screen gain correction matrices for various types of light emitting surface and test set-ups;
measuring the luminance or color values of the light emitting surface using the imaging light and color measurement system; and
calibrating the imaging light and color measurement system by correcting the luminance or color values measured thereby with the corresponding screen gain correction matrix.
4. The multi-point calibration method according to claim 3 , wherein the light emitting surface is a display device.
5. The multi-point calibration method according to claim 3 , further comprising the following steps:
measuring the luminance or color value of each of the light emitting area of the light emitting surface at a specific angle to the light emitting surface using a spot measurement instrument;
measuring the luminance or color values of the light emitting surface using the imaging light and color measurement system; and
creating the corresponding screen gain correction by calculating the luminance or color values measured using the imaging light and color measurement system and the luminance or color values measured using the spot measurement instrument.
6. The multi-point calibration method according to claim 5 , wherein the screen gain correction matrix is created by dividing the luminance or color values measured using the spot measurement instrument with the luminance or color values measured using the imaging light and color measurement system.
7. The multi-point calibration method according to claim 3 , wherein the screen gain correction matrices are used to create screen gain correction functions.
8. The multi-point calibration method according to claim 7 , wherein the screen gain functions are created by using a best fit algorithm for all points in the screen gain correction matrices over a domain corresponding to the size of the light emitting surface.
9. The multi-point calibration method according to claim 8 , wherein the screen gain correction functions are used to create screen gain correction matrices for all pixels of the imaging light and color measurement system.
10. The multi-point calibration method according to claim 3 , wherein the screen gain correction matrices for all pixels of the imaging light and color measurement system are created by interpolating between points of the corresponding screen gain correction matrix.