LEDs not rated for enclosed fixtures should only be used in fixtures open in the front, where the lamp’s lens is open on the sides and the rear, and should have at least 1/2″ space around the circumference of the lamp.
On the other hand incandescent light sources produce light by heating a filament until it grows red hot. Linear and compact fluorescent lamps use a UV discharge plus phosphor to produce the light. HID lamps use the ionization of gases in a discharge tube which in turn produce photons.
This is an elliptical region on the CIE chromaticity diagram that contains all the colors that are indistinguishable to the average human eye, from the color at the center of the ellipse. Adjacent ellipses are “just distinguishable” in terms of color. This system is used to refine the binning process of LED colors. Slight color differences in the appearance of LED light are measured in MacAdam ellipses or steps.
- Prefabricated chip on board which can be used for specific applications by luminaire manufacturers who design the heat sink and mounting conditions.
- Chip on board with an optical lens or diffuser as a prefabricated piece with or without integrated heatsink. That can be used by luminaire manufacturers to integrate into luminaire.
- Retrofit lamps to replace older (halogen) technology. This comes with an integrated heat sink and standard lamp base that can fitted directly into existing luminaires with a standard lamp holder.
- Prefabricated luminaires with an integrated LED light source and heat sink complete with luminaire housing that is available as a sealed piece. The driver may be integral in the housing or may be remote.
- SMD (Surface mounted diode) is a standalone chip on a ceramic base that can be integrated into various packages for linear LED strips or downlights.
- COB (chip on board) LED, which comes as a high powered chip in direct contact with a printed circuit board optimal thermal management.
- MCOB (multiple chips on board) LEDs, which are multiple COB LEDs integrated to form a single chip. This technology is used in LED bulbs and tubes.
- MCCOB (multiple chips and cups on board) packages, which are used for high bay fixtures and floodlights.
- Reduction in the production process.
- Simplification and reduction in the number of components.
- Introduction of new materials.
- Luminaire spacing and layout.
- Ways to prevent a view of the light source and minimize glare.
- Ventilation/cooling of LEDs
- Wiring access
- Access to LEDs in case of maintenance or replacement.
- Location of driver, if not integrated in luminaire.
- Switching / dimming capabilities, or control type and location.
- The lamp base / holder screw fixing position.
- The physical dimension of the LED lamp and how it fits into the existing housing.
- The electrical characteristics of LEDs compared to the existing system. (Main voltage, low voltage, control methods).
- The location and size of the light emitting surface in relation to the luminaire reflector and in comparison to the original light source.
- The light distribution, lumen output and other photometric properties like color temperature in comparison to the original light source.
- The heat generated by the LED during operation and the maximum operating temperature.
Constant current drivers fix the current of the system and vary the voltage depending on the load of the LED.
Constant voltage drivers require a fixed voltage, and the LED loads are added in parallel across the output of the driver until maximum output currents are reached.
Saves energy, because less energy is used for reduced output levels.
Extends life; the electronic components run cooler. This not only extends the life of LEDs but also increases the life of the phosphor coating that is used to produce white light.
Helps designers create ambient lighting presets to create mood settings.
Increases flexibility in usage of space. A brightly lit space for reading or an office space can turn into a presentation/conference area by dimming.
Increases productivity by enabling individual control of lights in order to reduce eye strain and fatigue, or to improve concentration.
- Reduction in luminous flux
- Color shift (change in color appearance)
- Reduction in life of the LED
- Use of micro prismatic technology to develop special diffusers that disperses light from individual LEDs. This system gives out homogeneous light with optimum levels of contrast avoiding any direct or reflected glare.
- Design of secondary reflectors systems; where the primary reflector, which will hide the view of the LED and direct the light into the secondary reflector that will distribute the light in the intended way.
- Use of a combination of TIR (total internal reflection) lenses / collimator lens, which that produce a parallel beam of light, and a facetted lens. This combination will distribute the light beam as intended.
- Heat buildup occurs as the luminaire is turned on, and as it cools down when it is switched off.
- Pressure changes caused by a change in altitude and environmental conditions during transportation in cargo holds or in planes.
- Thermal shock due to rain, snow or washing cycles.