| 摘要 |
PURPOSE:To enhance a light transfer efficiency by a method wherein a light- impermeable layer is laminated so as to cover a light-emitting face of a semiconductor of a P-N junction and a small hole through which light can be passed is made. CONSTITUTION:A light-impermeable layer 8 is laminated on a P-AlxGa1-xAs layer 5 and an insulating layer 6; it is a light-impermeable layer constituted of silicon oxide with which a paint is mixed; many small holes 8a which can emit a small-diameter light beam are made. An LED array 1A is connected to a substrate 20 by a die bonding operation or a wire bonding operation; it is arranged near a photosensitive drum 40. Each LED in the LED array 1A is driven selectively so as to emit light by a drive circuit on the basis of a picture signal; light is emitted from a face as a whole; the light is blocked by the light-impermeable layer 8 and is radiated from the small holes 8a. The light is focused on a photosensitive drum 40. |
