Benefits of LED technology
LEDs or Light Emitting Diodes have potentially replaced the traditional lighting source due to their cost and size advantages. It was initially used as indicator lamps in a number of electronic devices. However, the continuous development of LED technology has led to the embrace of this technology in all types of general lighting.
LEDs are extremely energy efficient and can use up to 90% less energy than conventional fluorescent bulbs. As such, they help greatly reduce energy costs. Due to low power consumption, LEDs are becoming popular light sources in remote areas using solar panels. LEDs also have a long lifespan of up to 60,000 hours compared to 1,500 hours for light bulbs. Plus, they’re durable and can withstand shock, vibration, and extreme temperatures. You can also improve safety by using LEDs as they produce 3.4 btu per hour compared to 85 for incandescent bulbs.
People are using LEDs in a variety of applications, including residential lighting, aerospace, architectural lighting, automotive, aviation, broadcasting, electronic instrumentation, entertainment and gaming, and more.
Especially in the micro projection system, the use of LED optics will increase over the years. This is because lighting uniformity and efficiency in spatial light modulators, or SLMs, are the two most important factors in measuring microprojection system performance. People often use a Conical Light Pipe (TLP) and a Square Compound Parabolic Concentrator (SCPC) as the beamformer in an LED-based microprojection system. With this, you will get SLM with even and efficient lighting.
However, TLP or SCPC has some disadvantages, the main one being the lack of compactness induced by the working length of TLP or SCPC for the illumination system. To overcome this problem, TIR or total internal reflection lenses can be used.
TIR lens definition
TIR or total internal reflection lenses are cone-shaped lenses that generally have rotationally symmetrical designs to distribute light in a rounded pattern. You can use TIR lenses to collimate the light or generate a preferred uniform illumination.
TIR lens manufacturing process
During the manufacture of TIR lenses, designers often do not pay attention to color uniformity, which also limits their application. However, you can address this issue by effective color mixing and using an integrated phosphor converted white LED module with a compact modified free form for compact size and high Angular Color Uniformity (ACU).
Manufacturers design total internal reflection lenses with an optimization method to combine and transfer most of the light emitted by the LED optics to a rectangular target plane or RTP that represents SLM. Typically, the TIR lens has six surfaces controlled by seventeen dimensional parameters. The design is carried out by optimizing dimensional parameters with general algorithms. To keep RTP on a rock-solid basis with pleasing lighting uniformity and efficiency, designers consider lighting uniformity and efficiency across RTP during the optimization process.
In the Tracepro program, the simulation result of the LED lighting system with the optimized TIR lens shows that the lighting efficiency and uniformity have reached 61.9%, 76% considering the angle of light limitation (15 degrees ).
You can make these lenses for multiple LED applications. The manufacture of different sizes of TIR lenses depends on their optical performance, so FWHM angles etc cannot be specified.