| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical head device in which light utilization efficiency can be improved more than conventional one, miniaturization, light weight, and low cost can be performed. <P>SOLUTION: The optical head device 100 is provided with a light source 11 emitting light, a 1/4 wavelength plate 12 converting straight line polarization to circular polarization, a cholesteric liquid crystal beam splitter 20 splitting incident light into a transmission beam and a reflected beam, an objective lens 13 condensing the incident light on an optical disk 15, and a photodetector 14 detecting a light signal. The cholesteric liquid crystal beam splitter 20 is provided with transparent substrates 21 and 22, orientation films 23 and 24, and cholesteric liquid crystal 25. <P>COPYRIGHT: (C)2008,JPO&INPIT |
