Used mainly as a spatial frequency low-pass filter for removing pseudo-signals from a camera.
【Digital Single Lens Reflex Camera】
Role of Optical Components
High image quality is realized by reducing the occurrence of patterns（moiré*1）and colors（false colors*2）that do not actually exist.
*1 Moiré = A geometric pattern that occurs when a pattern smaller than the pixel pitch of the image sensor (image element) is captured.
*2 False Color = A phenomenon in which colors (rainbow colors, etc.) that do not exist in the subject appear in the image.
Example of Flse Signal Removal
Without Optical Low-pass Filter
（Color Moiré Occurring Throughout the Entire Image）
With Optical Low-pass Filter
（Color Moiré is Removed）
Shot with Camera That
Does Not Use an Optical Low-pass Filter
Shot with a Camera That
Uses an Optical Low-pass Filter
In photo（1）, false colors occur at the wire mesh boundary, but in （2）, most of them have been removed.