Abstract: An apparatus is provided for measuring viewing angle characteristic of luminance and positional characteristic of a radiant object under measurement, by moving a condensing device and an imaging device relative to the object. The apparatus includes a first mechanism for moving the light receiving elements of the condensing device while keeping constant the solid angle subtended by the light receiving element at the radiant area. A second mechanism is provided for moving the imaging device in association with the condensing device, while maintaining thereon the image of the radiant area. A memory is provide. A circuit is provided for calculating viewing angle dependent and position dependent characteristics. A display device is provided for displaying radiance characteristic and distribution characteristic of the object and the result of evaluation of the calculated characteristic of luminance.

Abstract: A method and an apparatus for measuring viewing-angle dependent luminance (luminance characteristic) of an LCD panel by condensing radiation from LCD pixels by means of a condensing device which includes a mirror, and by forming a real image of the pixels on an CCD imaging device. Correct luminance characteristic of the LCD panel is calculated by making a correction of the data thus obtained using a predetermined condensing function. The correction removes blurring of data due to condensing effect of the condensing device, thereby preventing degradation of the resolution of the angular luminance measurement apparatus. The condensing device and the CCD imaging device are moved depending on the viewing-angle of the pixels. When the intensity of light entering the condensing device decreased by the move, the correction is performed.