| 摘要 |
<p>An optical filter for filtering a predetermined spatial frequency component of a light wave, comprising a birefringent film (71) disposed between birefringent plates (72, 73) each for separating an incident light beam into two light beams and adapted to change the velocity of the incident light depending on the direction of the vibration of the light wave, wherein birefringent film portions (711, 712) constituting the birefringent film (71) are formed on at least one of the surfaces of the birefringent plates (72, 73), and the birefringent plates (72, 73) are so integrated into one piece that the birefringent film (71) formed on the surface and composed of the birefringent film portions (711, 712) is interposed therebetween.</p> |
