| 摘要 |
PROBLEM TO BE SOLVED: To provide a projector optical system that completely shields against light reflected from a prism face.SOLUTION: In a projector optical system that decomposes or composes light by a beam splitter and reflects the light by a DMD, thereby projecting it onto a screen, a clearance between the two prisms of the beam splitter is formed in the shape of a wedge, an angle between the normal of each prism with respect to a prism face and incident light beam is set to 72 degrees or less, and a reflection preventing film is provided on the prism face so as to continuously increase the degree of refraction index. Instead of forming the reflection preventing film, a minute projection recess cycle structure body can be formed on the prism face. |
