Lens Tech on Survival Gear Lighting

What is a TIR lens

Jan. 16, 2017

Most typical lenses in the LEDiL standard product range are the cone-like lenses. These lenses are often called TIR lenses as a big part of their design relies on total internal reflection. Typically TIR lenses are rotationally symmetrical designs which give a nice round light distribution. The lenses can be designed in arrays for multiple LEDs or have mechanical details included to aid mounting.

Total Internal Reflection

Reference: http://www.ledsmagazine.com/articles/print/volume-9/issue-2/features/tir-optics-enhance-the-illuminance-on-target-for-directional-led-modules-magazine.html

TIR Lens VS. Reflector

The basic working principle is the same for both TIR lenses and reflectors, but TIR lenses have more control over light. With reflectors a big part of the light doesn’t “touch” the reflector and this light can’t be controlled in any way. This difference can easily be seen with tight spot optics as reflectors usually don’t have as sharp a cutoff as TIR lenses. TIR = Total Internal Reflection Lens TIR lens’ typical light distribution has a sharp cut-off.

Reflectors produce much softer cutoff even if the viewing angle is same. Relative intensity of LEILA-RS lens. Tight spot lenses produce typical “spike” of light with very tight cutoff. Relative intensity figure of REGINA spot reflector. Note how light is spread into wider angles.