Can you see infrared light with phone camera?

Phone Cameras and the Visible Spectrum

Cameras on smartphones, unlike the human eye which relies more on light, are constructed with the focus of capturing the light spectrum otherwise known as the invisible light. This spectrum roughly covers wavelengths from about 400 nanometers (violet) to 700 nanometers (red) with the human eye being the center focal area. However, besides the light that can be seen, there exist other many forms of electromagnetic radiation, for instance, ultraviolet and infrared which go beyond the visible spectrum.

What is infrared light?

To begin with, infrared light is a type of electromagnetic radiation that the human eye cannot see. This is because it is situated outside the visible light range. Any light that is seen can be considered as ‘visible’ regarding the infrared spectrum as it has wavelengths within the range of 700 micrometers and one millimeter. But this is however not the case with all devices as some specially built sensors can recognize and hide infrared light.

How camera sensors work

Different smartphone models use different sensors but most notably CCD or CMOS sensors. These components are basically photoconductive sensors, which take incoming photons as an input and convert it into electrical signal which is later used to algorithmically create an image. However, it should be noted that although these photosensitive elements are designed to retrieve the maximum amount of light from the visible spectrum they are also capable of detecting infrared light.

The role of infrared filters

In order to make the photos taken display correct and natural colors, manufacturers usually install an infrared cut filter (IR Cut Filter) so that the majority of the infrared light from hitting the sensor and hence reduce the effects of infrared light on the final output. On the other hand, not all mobile phones contain this filter themselves, or the filter’s only function is to reduce the infrared light.

Actual observation attempts

The radiation of infrared light is invisible to human vision, however, its effect can be noticed in some cases with the use of mobile cameras. As for the latter, one can take a mobile phone and point a remote control towards its camera; there is a number of instances in which bright flashes can be seen through the camera. The reason behind this occurrence is that a remote control operates by emitting a modulated near-infrared beam which a mobile camera can pick up.

Mobile cameras, more often than not, operate by capturing visible light spectra. However, there are instances, rare ones that allow for infrared images to be captured indirectly, through seeing how normal phone cameras operate. However, it is essential to remember that the interpretation of pictures taken from cell phones equipped with infrared light are not comparable to those captured by professional infrared cameras. 

Due to the dependent nature of lights, the quality and internal make-up of the camera in question, the outcome of photography by infrared light may differ greatly. Therefore, for work that demands reliability and accuracy dealing with infrared light, professional cameras tailored for such work can be helpful.