Patent ID: 6023374
Filing Date: 2000-02-08
Classification: G02B,H04N

Abstract:
A beam path expander comprising:an incidence plane forming an anti-reflection plane to admit light having a specific wavelength into a medium having arbitrary refractive index without reflection;a first total reflection plane that is cut into the beam path expander at a total reflection angle determined by the refractive index of said medium for total-reflecting the light admitted from said incidence plane in said medium;a second total reflection plane that is cut into the beam path expander at said total reflection angle for total-reflecting the light reflected from said first total reflection plane at said total reflection angle in said medium;n third total reflection plane(s) (n=0, 1, 2, . . . ) cut into the beam path expander at said total reflection angle for forming a specific light path by total-reflecting the light reflected from said second total reflection plane into said medium; andan outlet plane forming an anti-reflection plane to make the light that is reflected from said third total reflection plane exit the medium.