To output or diffuse the light radiated from a light source correspond ing to the range of illumination.
A number of convex lenses are formed in a two-dimensional state on one side of a transparent substrate to comprise a lens array plate 2b, and a sealing layer 2c is installed thereon to constitute a first diffusion substrate 2. A second diffusion substrate 3 having the same structure is supported to face the first diffusion substrate 2, wherein a center distance between the convex lens of the diffusion substrate 2 and the convex lens of the diffusion substrate 3 can be adjusted within a certain range including (f1+f2) (f1 and f2 are focal distances). If the center distance is adjusted to (f1+f2), the parallel light from a light source 5 is converted into parallel light after passing through the lens array plates 2b and 3b. If the distance between both diffusion substrates is adjusted to a value different from this, the light after passing through the second lens array plate 3b becomes diffused light.
SHINOHARA MASAYUKI
AOYAMA SHIGERU
| JPH0269405U | 1990-05-25 |
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