Infrared camera technology is divided into passive infrared camera technology and active infrared camera technology. Passive infrared camera technology leverages the principle that all substances above absolute‑zero temperature emit infrared light. Human bodies and heat‑generating machinery emit strong infrared radiation, while other objects produce weak infrared signals. Special infrared cameras can realize night‑time surveillance based on this principle. Then how should we select infrared lamps for infrared cameras? What factors should be taken into account? This article elaborates on this topic as follows.

Methods and key considerations for selecting infrared lamps for infrared cameras are listed below:

1. Power SupplyThe power supply for infrared lamps deserves careful attention. The operating current of infrared diodes is highly sensitive to supply voltage, and DC voltage attenuation varies with cable length. When multiple infrared lamps are at vastly different distances from the control room, centralized DC12V power supply may result in higher voltage for lamps close to the control room and lower voltage for those far away. Coupled with deviations in power‑supply voltage adjustment, infrared lamps receiving excessive voltage may suffer shortened service life or even burnout, whereas lamps with insufficient supply voltage will deliver inadequate emission power.
2. Lens SpecificationsIt should be noted that infrared light features a longer wavelength. When passing through ordinary non‑infrared lenses, its focal point is slightly deeper than that of visible light. Consequently, images captured at night with infrared lamps may appear slightly out of focus.
3. Manufacturers or VendorsSome equipment manufacturers or vendors only provide power ratings instead of the irradiation distance of infrared lamps. Though this may reduce workload for suppliers, it is a rather ambiguous indicator. Apart from generating infrared light energy, power consumption also includes heat losses from power supplies, circuits, light sources, as well as infrared transmittance loss of filter glass sheets. Infrared lamps with identical power ratings can have drastically different irradiation distances.
4. Housing Protective CoverProtective covers also exert influences on infrared lamp performance. When infrared light travels through different media, its transmittance and reflectivity change accordingly. Different window glasses, especially anti‑frost coated glass, cause varying degrees of attenuation to infrared light.

With the rapid development of infrared night‑vision systems, more manufacturers will join the supply of infrared lamps. Nevertheless, infrared products are not as simple as some people assume. Suppliers differ greatly in technical capability and testing equipment. Users are advised to make thorough comparisons and prudent selections.