Abstract: A projection lens includes a first lens group, a second lens group and an aperture stop. The first lens group is disposed between a reduced side and a magnified side. The second lens is disposed between the first lens group and the magnified side. The second lens group has a light incident surface, a reflective surface and a light emitting surface, the light incident surface faces the first lens group, the light emitting surface faces a projection surface, the light incident surface, the light emitting surface and the first lens group are disposed at a single side of the reflective surface, and at least one of the light incident surface, the reflective surface and the light emitting surface is a freeform surface. The aperture stop is disposed between the first lens group and the second lens group. Moreover, a projection apparatus including the projection lens is also provided.

Abstract: The present invention provides an LED device with a flip chip structure. The LED device comprises an insulating substrate, an LED flip chip, a molding compound, a first conductive element, and a second conductive element. The LED flip chip is electrically connected to the connection pads on the insulating substrate via the two conductive elements. The P-type and N-type electrodes are connected to the P-type and N-type electrodes layers, respectively. The invention need not require a conventional wire bonding process. It not only increases the yield rate of the product but also makes the product more compact.

Abstract: An LED includes an insulating substrate; a buffer layer positioned on the insulating substrate; an n+-type contact layer positioned on the buffer layer, the contact layer having a first surface and a second surface; an n-type cladding layer positioned on the first surface of the n+-type contact layer; a light-emitting layer positioned on the n-type cladding layer; a p-type cladding layer positioned on the light-emitting layer; a p-type contact layer positioned on the p-type cladding layer; an n+-type reverse-tunneling layer positioned on the p-type contact layer; a p-type transparent ohmic contact electrode positioned on the n+-type reverse-tunneling layer; and an n-type transparent ohmic contact electrode positioned on the second surface of the n+-type contact layer. The p-type transparent ohmic contact electrode and the n-type transparent ohmic contact electrode are made of the same materials.

Abstract: A LED package is comprised of a flat panel base and three LED dies. The flat panel base is composed of a first golden film area, a second golden film area, a third golden film area, a fourth golden film area, a first connection area, and a second connection area, wherein the first connection area and the second connection area are connected to the first golden film area. The first LED die is attached on the flat panel base by flip-chip mounting, wherein an anode of the first LED die is connected to the first golden film area, and a cathode of the first LED die is connected to the second golden film area. The second LED die is attached on the flat panel base by flip-chip mounting, wherein the second LED die is composed of an anode connected to the first golden film area, and a cathode connected to the fourth golden film area.

Abstract: A LED package is comprised of a flat panel base and three LED dies. The flat panel base is composed of a first golden film area, a second golden film area, a third golden film area, a fourth golden film area, a first connection area, and a second connection area, wherein the first connection area and the second connection area are connected to the first golden film area. The first LED die is attached on the flat panel base by flip-chip mounting, wherein an anode of the first LED die is connected to the first golden film area, and a cathode of the first LED die is connected to the second golden film area. The second LED die is attached on the flat panel base by flip-chip mounting, wherein the second LED die is composed of an anode connected to the first golden film area, and a cathode connected to the fourth golden film area.

Abstract: A nitride light emitting diode is fabricated on a transparent sapphire substrate. The LED is then mounted upside-down on a conductive silicon substrate with a bottom electrode to serve as the output terminal for the cathode of the LED. The LED die is partially etched to expose the anode of the LED, where a top electrode is formed. In comparison with conventional LED structure with both electrodes located on top of the die, moving one electrode to the bottom allows more light to be transmitted upward and reflects the light incident downward. For equal amount of light emission, the new structure occupies less area.

Abstract: A surface-emitting AlGaInP LED is disclosed. The LED uses a GaP layer as a window layer to eliminate the current crowding effect, or may has an ITO window layer and use GaP, instead of GaAs, as the substrate to eliminate the current-crowding effect and avoid the emitted light being absorbed by the substrate. The GaP layer is bonded to the double hetero-structure epitaxy layer by a wafer bonding technique. The present invention, however, provides a manufacturing procedure which is easier and more reliable to handle than prior arts.

Abstract: A surface-emitting AlGaInP LED is disclosed.

Abstract: A surface emitting AlGaInP LED having an ITO layer as a window layer to eliminate the current crowding effect, and an ohmic contact layer between its double hetero-structure of AlGaInP and the ITO layer, so that ITO can be utilized with the double hetero-structure of AlGaInP.

Abstract: A surface emitting AlGaInP LED having an ITO layer as a window layer to eliminate the current crowding effect, and an ohmic contact layer between its double hereto-structure of AlGaInP and the ITO layer, so that ITO can be utilized with the double hereto-structure of AlGaInP.