Light Source Safety Calculator
One important aspect of any design is user safety. This is especially important when using light sources like lasers and LEDs that may be observed by the naked eye. Disregarding safety can lead to product recalls, lawsuits, and harm to users. To protect users, a number of standards related to light and eye safety have […]
TIR Lenses: 3 Essential Design Concepts for Optimal Light Control
Working principle of TIR lenses A TIR lens works on the principle of total internal reflection. When light reaches an interface between two materials with different refractive indices and the correct angle of incidence, there is refraction (bending of a light ray from its original path). As light travels from a medium with a higher […]
5 best materials for LED illumination optics
Freeform lenses (including TIR lenses) and lightpipes are the two most common types of LED illumination optics. They can be made using injection molding and are affordable. Glass materials are not common for general illumination, but are used for spherical lenses or aspheres in devices such as optical instruments with Abbe or Köhler illumination. In […]
Laser Beam Caustic: Explained
One parameter that can be used to evaluate the quality of a laser beam is what’s called a Beam Caustic. A caustic, in general, is an “envelope” that defines the extent of a beam of light after they have been refracted (or reflected ) by a curved surface. As the light beams propagate they cross […]
5 Tricks to Control Stray Light
When designing an optical system, an optical engineer needs to consider where the light to be directed, and also where the light shouldn’t be propagating. We call this unwanted light: stray light. Stray light is a major limiting factor in many imaging systems. When stray light enters the system, it degrades the signal-to-noise ratio or […]
Understanding the optics behind a PAPI light
In a previous article we talked about Aviation Light Optics. and discussed a runway light system called Precision Approach Path Indicator (PAPI). Now we would like to go more in detail into PAPI design and describe their design requirements. The PAPI system is a set of four light sources that help the pilots correct the […]