| 摘要 |
PURPOSE:To lessen a thickness of a low-pass filter with the removal of a moire without lowering resolution by forming a low-pass filter from a liquid crystal element or an electro-optics element having birefringence. CONSTITUTION:Using the liquid crystal element 5, an orientation of which (crystal axis direction) is slanting towards an optical axis, the low-pass filter 6 is formed. The difference between indexes of refraction for both an abnormal and normal light of the liquid crystal element 5 is so large that it is possible to prepare the thin low-pass filter. And the low-pass filter 6 setting between a camera lens 2 and CCD 3 can remove the moire by cutting high frequency components with birefringence. |
