| 摘要 |
PROBLEM TO BE SOLVED: To provide a multiplexer, in a laser projector, of light beams of a plurality of wavelengths of red/green/blue or near infrared that is applied to a mobile phone and vehicle, has an environmental resistance, has a high efficiency, is manufactured at a low cost, and is compact.SOLUTION: The multiplexer of a plurality of wavelengths includes a hollow reflection type light guide formed by pasting a cover plate 120 having a reflection film on a substrate 110 having grooves 112 of a pattern having a side surface reflection film 113. The multiplexer has an environmental resistance and a high efficiency because it has a characteristic of non-absorption due to the hollow shape, non-dependence on the wavelength, and non-dependence on the light beam wavelength and lateral mode due to the whole reflection film disposed on the side surface to the incident light at almost whole stereoscopic angle. Due to fiber output of the multiplexer, the light source can be separated from an irradiation head. The method of producing the hollow light guide employs the pattern etching and a semiconductor process such as thin film evaporation, and can support mass production of low cost and high reliability.SELECTED DRAWING: Figure 1 |
