| 摘要 |
PURPOSE:To obtain a uniform LED output even when an LED array has large variance in light emission intensity by arranging a photosensitive material for the shading correction of the LED array on the front surface of the LED array. CONSTITUTION:A negative photosensitive material 7 is fixed on the light emission window 16 of the LED array 15. All LEDs in the LED array 15 are turned on with the same electric power to expose the photosensitive material 17 firstly. The photosensitive material 17 is developed and fixed. At this time, the array 15 has variance in light emission output and the density of the exposed photosensitive material 17 is high where individual LED light of the array 15 is intense and low where the light is weak. Thus, the photosensitive material 17 is fixed blackly where it is in front of an LED, so the light transmittivity of the photosensitive body 17 is low although the transmittivity of the photosensitive body 17 is high where the quantity of light from the LED array is small. Therefore, the emitted light from the array 15 is transmitted through the photosensitive body 17 to obtain the uniform output. |
