IR Corrected Lenses

An IR Corrected lens, also known as an infrared corrected lens, is a sophisticated type of optical lens that has been fine-tuned to provide clear and sharp images in both visible and infrared light spectrums. This is particularly important in surveillance cameras that operate around the clock, as typical lenses tend to lose focus when switching from daylight (visible light) to infrared illumination at night.

When a conventional lens is exposed to infrared light, the different wavelengths of light do not converge at the same point after passing through the lens, leading to what is known as chromatic aberration. This results in out-of-focus images and degraded overall image quality when illuminated by IR light, especially at the peripheries.

To counteract this, IR Corrected lenses are designed with special optical elements that compensate for the focus shift between visible and infrared light. This is achieved through the use of materials with particular refractive indices and specially designed lens coatings that help to focus both spectrums of light onto the same plane, which ensures that the camera can maintain sharp focus whether the scene is lit by sunlight, indoor lighting, or infrared light sources.

Comparison of MTF test images during the day (top) and at night (bottom)

Several ITS lenses independently developed by ChuangAn Optoelectronics are also designed based on the IR correction principle.

There are several benefits to using an IR Corrected lens:

1. Enhanced Image Clarity: Even under varying lighting conditions, an IR Corrected lens maintains sharpness and clarity across the entire field of view.

2. Improved Surveillance: These lenses enable security cameras to capture high-quality images in a variety of environmental conditions, from bright daylight to complete darkness using infrared illumination.

3. Versatility: IR Corrected lenses can be used across a wide array of cameras and settings, making them a flexible choice for many surveillance needs.

4. Reduction of Focus Shift: The special design minimizes the focus shift that normally occurs when switching from visible to infrared light, thereby reducing the need for re-focusing the camera after daylight hours.

IR Corrected lenses are an essential component in modern surveillance systems, particularly in environments requiring 24/7 monitoring and those that experience drastic changes in illumination. They ensure that security systems can reliably perform at their best, regardless of the lighting conditions present.