Optical Low-Pass Filters

What is OLPF?
Graph of spectral characteristics
What else we can do

Illustration-1

As the demand for high-quality images continues to grow, OLPFs have the potential to improve image quality in a wide range of consumer electronics, including digital
cameras, smartphones, and tablets.

Illustration-2

OLPFs have the potential to improve the image quality of medical imaging devices, such as computed tomography (CT) scanners, magnetic resonance imaging (MRI) systems,
and ultrasound equipment.

Graph of Typical Spectral Characteristics

Vacuum evaporation involves placing materials in a vacuum and evaporating them by creating a high-temperature environment. The evaporated material adsorbs and forms a thin layer on the surface in the vacuum. This process takes place in a vacuum environment, eliminating interference from air and other substances.
Vacuum evaporation offers several advantages, such as high-precision film formation, fast deposition speed, and high quality crystal formation. This technology is used in many areas, including semiconductor device manufacturing, optical device manufacturing, electronic device protection, and surface treatment.

See a list of spectral characteristics graphs

What else we can do: Adhesive Techniques

Quartz substrates, which typically have high mechanical strength, thermal stability, and light
transparency, are used as electrically stable platforms.
By bonding a quartz substrate with C-MOS sensors, semiconductor devices that receive external
stimuli such as light or electromagnetic waves and detect signals, it enables us to:
(1) Suppress noise and signal distortion caused by external vibrations and shock.
(2) Increase sensitivity by improving light transmittance.
(3) Operate the C-MOS sensor stably at high temperatures.

OLPF holders are typically fixed to the lens by means of adhesives. The use of an appropriate adhesive allows the filter to be held securely in place while maintaining high quality optical
performance.

This and that of Optical Low-Pass Filter (OLPF)

The filter removes non-existent moiré patterns by taking advantage of birefringence, a property of
quartz crystal.

In a digital camera with light-receiving elements (pixels) arranged in a regular pattern, the superposition of the resolution pattern of a subject with a regular pattern and the spacing between the light-receiving elements can cause a pattern that does not exist in reality, called 'moire'.