| 摘要 |
<p>PROBLEM TO BE SOLVED: To improve design by accomodating a reflection-type volume phase hologram inside of a lamp body, and mounting a diffusion plate or the like on a rear face of the same, for clearly indicating the display images of the different patterns in the same area between the daytime and the night time. SOLUTION: A color filter 11b for transmitting the light of wavelengths different from that of the light, transmitted through a color filter 11a, and a diffuse reflecting plate 13 having a reflecting film 12 on at least one face thereof, are stacked on a rear face of a reflection-type volume phase hologram 4. In the daytime, though the strong external light such as the sunlight enters into the lamp body 1b, it is transmitted through the hologram 4 as it is, because the direction and angle of the light do not contribute to the diffraction of the hologram 4. The transmitted light is transmitted through the filter 11b, enters into the reflecting plate 13, further diffused and reflected to the outside of the lamp body 1b. Here, the indicating lamp indicates the pattern engraved on the reflecting plate 13. At night time, when a valve 5 is lit, the direction and angle of the beam contributes to the diffraction of the hologram 4, thereby a hologram three-dimensional image 10 can be indicated.</p> |
