Advanced Optical Design

December 28, 2013

By Chris McCaslin, Engineering Director, Light & Motion

Most of our products use mirrored reflectors and optical-quality glass, an optical solution which we have found to be the most efficient, and which creates the most beautiful beam patterns.  Most portable lighting manufacturers use off-the-shelf molded reflectors made of clear plastics.  Termed T.I.R., for Total Internal Reflection, these reflectors focus light by bending it internally.  Our experimentation has shown that most of these solutions project light unevenly—leaving unintended bright spots and dark spots, called artifacts, in the beam.  These spots can show up in your photography, and can be distracting bouncing down a mountain trail.  TIRs have also proven less efficient, absorbing or scattering light that we want to focus on the subject.

Using both advanced optical software and practical experimentation with varying shapes of prototype reflectors, we work to concentrate light where you need it.  In some cases we do use TIR reflectors, for instance when a very tight spot beam is required in a very tight space, something that TIR’s excel at.  For our Sola and GoBe Search spot beams, we experimented with many reflectors before settling on a design that provided a sufficiently tight spot.

In most products, in-house design of mirrored reflectors creates the brightest possible lights, and allows us to create special features.  These include integrated side lights from a single LED, and shaping the beam of each emitter in a single- or multi-LED head for optimal use on a bicycle.  You can see this in Taz and Seca, and in our taillights that provide industry-leading visibility from all around your bike.  In some cases we use peening to scatter just the right amount of light to soften hard edges in the beam.

And in a few products, we simply get out of the way, putting the LED as front and center as possible, to provide the widest, most even beam pattern possible.

These small differences all work to blend light seamlessly into your environment.  Our goal in optics design is for you to forget the light there, and to remember the experience, not your lighting.