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You can use one of our IP cameras to extend your vision into the near infrared, which is beyond the range of what our eyes can detect. Visible light is just a small portion of the electromagnetic spectrum. Visible light has wavelengths ranging from roughly 400 to 700 nm (1 nm = 10-9 m). The perceived color of the light changes with wavelength (see Figure 1). Shorter wavelengths have higher frequencies and higher energy. Longer wavelengths have lower frequencies and lower energy.
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| Figure 1. The visible portion of the electromagnetic spectrum. Longer wavelengths have lower energy. Note that wavelength is given in ìm; to convert to nm, simply multiply by 1000. |
Below 400 nm is the ultraviolet region of the electromagnetic spectrum. Ultraviolet light is not visible, but has higher energy than visible light (think of sunburn). At even shorter wavelengths are x-rays and beyond that, gamma rays, each with increasing frequency and energy. Infrared light is beyond the other end of the visible spectrum, with wavelengths longer than about 700 nm. This light has lower energy than visible light. Beyond the infrared region of the spectrum are microwaves, and then progressively longer-wavelength (and lower-energy) radiofrequency bands: TV and FM radio, shortwave and AM radio, and finally aircraft and shipping bands.
Infrared light is often divided into three different "bands": near, mid, and far infrared. For infrared photography, it is the near infrared (NIR) band that is detected. As with visible-light photography, NIR photography is capturing reflected light (not intrinsic heat of objects, which is emitted at longer IR wavelengths). | 
