Why Secondary Optics Makes Sense for LED Designs

By Chris MillerJune 17, 2016

This is part three of our four part series on LightFair 2016. 

Industry reports show the secondary optics market to be the single biggest growth opportunity in lighting components, growing to $6.9 billion in 2023. Not surprisingly, secondary optics showed up many times on the floor of the LightFair International event this year.

So what are secondary optics and why are they gaining prominence in LED designs?

Optics are components that are used to control the light output. As LEDs are directional light sources, designers usually use secondary optics to meet the specific and demanding needs of a lighting application.

Why Should One Use Secondary Optics?

Certain applications require specific angles, as well as different beam shapes. Secondary optics are used to get that angle. It is usually mounted on a holder and attached directly onto or around the LED. Secondary optics are used to deliver beam of light that has large optical viewing angle and circular cross-section. Reflectors are generally fitted on the lenses to improve the light beam. This provides a focused lighting effect.

Compelling Benefits that Make Secondary Optics an Integral Part of a Lighting Application

The main benefit of mounting secondary optics is higher efficiency and improved lighting. Primarily, it is used to control the photometric performance of LED lamps and luminaires. This particularly enhances the performance and efficiency of lamps and luminaires. It can be fitted in a range of different applications, where the need is to angle the LED light beam perfectly without wasting any light.

In particular applications, the LEDs directional light from a primary optics is often not sufficient. This is often seen where the target plane of lighting is more than a distance of 0.5 m. In such cases, secondary optics help designers collimate the light beam to a farther distance.  It also gives the flexibility to improve spatial uniformity and color, while providing the scope to customize the beam according to the photometric needs. Practically, it is believed, even the most efficient light sources seem to be useless without high-quality secondary optics.

Determining Characteristics of Secondary Optics that Influence Higher Efficiency

The key feature of secondary optics is perhaps the flexibility it offers in designing. If a diffuser is integrated into the product design from the beginning, there will be no need to further redesign the secondary optics in a case that requires different beam angle of light. If just one reflector or TIR secondary optic is required, then only one mold needs to be manufactured, instead of many. This, through a single stock keeping unit (SKU), reduces the inventory costs significantly.

The secondary optics, when used with a diffuser, can be fitted in multiple installations. The main objective of the ‘add-on’, is to correct the intensity and non-uniformity in color, at a specified target plane. Another key function of secondary optics is to ensure an environment where the light is spread evenly without sacrificing the intensity. The increase in light intensity is achieved by redirecting the unused light from the sides, resulting into higher PAR and penetration.

Flexible Design Approach

In recent times, it’s much easier to integrate secondary optics in a LED design. There are several tools available, however the basic tool used by most of the designers developing lamps and luminaires, is the optical and lighting simulation software. Besides, there’s an array of packages that are now compatible with the bi-directional transmittance distribution function data that decides the behavioral pattern of the light in a LED module.

Want more information on secondary optics and products WPGA offers? Check out our trusted secondary optics suppliers and the resources they have available:

Have questions? Contact a WPGA Lighting Solutions Expert today at (888) WPG-8881!