The DieMount Spotlight LED are fabricated with the technology of microstructured submounts like the fiber-chip coupled products, too. But instead of coupling the light to a light guiding waveguide, the spotlight setups couple the light from the metallic microreflector to a parabolic plastic reflector. The plastic reflector is a geometrical continous extension of the metallic micro reflector and reflects the light at its borders by total reflection. The combination of metallic and plastic reflector acts like a long parabolic reflector with the LED die in the focal point.
The spotlight LED setups emit the complete LED light with high efficiency to a small solid angle of typically ±3-4°. The light losses as typical for other LED packages at larger angles to the optical axis are avoided to a large extent. Optical ray formation is done by the combination of the metallic reflector around the LED die and an inserted plastic reflector acting by total reflection.
The LED package design allows the very efficient illumination of distant objects. LED driver currents can be low with a long LED lifetime and a low power consumption as a consequence.
Very important for many applications is the spotlight attribute to emit “cold light” without parts in the infrared spectrum. This allows the application in combination with temperature sensitive materials, close to temperature sensitive sensors or food products like e.g. chocolates.
When the spotlight LED was developed in the first step standard LED dice with about 12mil die size were used. The table below shows the corresponding standard spotlight LED. Today this setup is available as OEM product only. The new design PowerLED spotlight (see table below right) comprises an about 40mil LED die and substitutes the standard spotlight LED. The light radiation radiation of PowerLED spotlight is about 10 times higher than the radiation of the standard spotlight LED.
The new development of PowerLED spotlight bases on PowerLED dice with 40mil die size and a typical maximum current of 350mA. It requires a heat sink to remove about 1W electrical power loss. The heat sink unit is made of aluminium. It is thermally connected to the metal submount and encloses the plastic reflector. As the heat generating LED die is thermally well connected with the submount, the system of LED die, submount and heat sink is a unit that doesn’t need further cooling. No additional aluminium printed circuit boards are required.
The LED module can be connected without the necessity to take care of thermal heat dissipation. The connector system of choice for all DieMount PowerLED modules is the edge card connector according to the SFP standard. SFP connectors are used in volume for telecom and datacom applications and are low cost as a consequence. Each SFP connector comprises 20 contacts that can be used to privide seperate contacts for LED modules of different colour. Even a temperature sensor and a monitor diode for brightness control is feasible.
Please find the details of the SFP connector system for power LED modules in the data sheet “PowerLED SFP connector“.
Standard Spotlight LED
Main application for standard spotlight LED is the efficient illumination of small objects. The spotlight setup couples nearly all the light from the LED die to the small radiation angle. As the power loss is below 150mW no seperate heat sink is necessary. The standard spotlight LED is available as OEM product only.
Technical data of standard spotlight LED