Introduction
Have you noticed that some security cameras show color during the day but switch to black‑and‑white at night? That's thanks to an IR‑cut filter. This small optical component blocks infrared (IR) light from reaching the image sensor. Why block IR? Because while IR is invisible to our eyes, camera sensors are very sensitive to it. Without an IR‑cut filter, colors look washed out, and images have a pinkish tint. But for night vision, you want IR to pass through. That's where dual IR‑cut switching comes in. At Sincere, we've been manufacturing cmos module camera solutions for over 30 years, including night vision camera module designs. This article explains what an IR‑cut filter is and how it works.
What Is an IR-Cut Filter?
An IR‑cut filter is a glass or plastic element placed between the lens and the sensor. It blocks infrared wavelengths (700–1100 nm) while letting visible light (400–700 nm) pass. This ensures the camera captures colors as our eyes see them. Without it, a white shirt might look purple, and grass could turn brownish.
Why Is IR Light a Problem?
Camera sensors (CMOS or CCD) see a wider spectrum than humans. They detect IR as extra brightness. In daylight, IR mixes with visible light, causing unnatural colors. A cmos module camera needs an optical filter to separate them.
How Dual IR‑Cut Switching Works
A fixed IR‑cut filter blocks IR all the time. That gives good color but no night vision. Dual IR‑cut switching solves this with a small electromagnetic actuator that moves a filter assembly:
Day mode: The IR‑cut filter is in place → accurate colors.
Night mode: The filter is retracted (or replaced by clear glass) → IR light reaches the sensor. An IR illuminator (LED) provides invisible light, and the camera sees in black‑and‑white.
The switching is automatic, based on ambient light. Such modules are called IR‑cut removable (ICR) cameras.
Applications
Security and Surveillance
Most outdoor security cameras use dual IR‑cut switching for accurate color by day and clear night vision. A night vision camera module without this would either have poor color or no night vision.
Automotive Inspection
An automotive inspection camera module used in a garage may not need night vision. But for under‑carriage or engine inspection in dark areas, dual IR‑cut switching lets the camera see in complete darkness using built‑in IR LEDs.
USB Cameras
Many camera usb modules for security or machine vision include IR‑cut filters. Some high‑end USB cameras offer dual IR‑cut switching for day/night operation.
Autofocus Camera Modules
An autofocus camera module can also include an IR‑cut filter. In night mode, when the filter is removed, focus may shift because IR light focuses at a different plane. Good designs compensate with IR‑corrected lenses or autofocus.
Fixed vs. Dual IR‑Cut Switching
| Type | Daytime Color | Night Vision | Complexity | Cost |
|---|---|---|---|---|
| No IR‑cut filter | Poor (reddish) | Good | Low | Low |
| Fixed IR‑cut filter | Excellent | None | Low | Low |
| Dual IR‑cut switching | Excellent | Excellent | Higher | Moderate |
For a camera that needs both accurate color and night vision, dual IR‑cut switching is the standard.
How to Choose
Do you need night vision? If the camera works only in well‑lit areas, a fixed IR‑cut filter is fine. For darkness, choose dual IR‑cut switching with IR LEDs.
Check the switching mechanism: Electromagnetic ICR (IR‑cut removable) is reliable and fast. Motorized wheels are slower and less durable.
Consider focus shift: When the filter is removed, focus changes. High‑quality night vision camera module designs use IR‑corrected lenses or autofocus.
For USB modules: Many camera usb modules with dual IR‑cut switching are plug‑and‑play UVC devices. They switch automatically.
Sincere's IR‑Cut Filter Modules
At Sincere, we design camera modules with fixed and switchable IR‑cut filters:
IR‑cut filter: Fixed filters for accurate color in controlled lighting.
Automotive inspection camera module: Rugged modules with dual IR‑cut switching for garage and field use.
Camera usb modules: UVC‑compliant USB cameras with automatic day/night switching.
Cmos module camera: Custom sensors paired with IR‑cut filters for optimal spectral response.
Autofocus camera module: Autofocus modules with IR‑corrected lenses and switchable IR‑cut.
Dual IR‑cut switching: Reliable electromagnetic ICR designs.
Night vision camera module: Complete solutions with IR LEDs and switchable filter.
Our manufacturing includes Class 10/100 dust‑free workshops and Active Alignment (AA) for perfect filter‑sensor alignment.
Summary
An IR‑cut filter blocks infrared light to give accurate color in daytime. For cameras that need both good color and night vision, dual IR‑cut switching moves the filter in and out automatically. This technology is essential for security cameras, automotive inspection camera module, camera usb modules, and night vision camera module designs. When choosing a cmos module camera or autofocus camera module, decide whether you need fixed or switchable IR‑cut filtering.
At Sincere, we provide custom IR‑cut filter solutions for your application. Contact us to discuss your requirements.
