Abstract: An electrodeless lamp (10) for producing an intense beam of light includes a concave lamp body (11) that surrounds the lamp interior. A gas, such as sulfur or selenium or compounds thereof, is contained within the lamp body (11) for forming a plasma light source. The concave lamp body (11) has a reflecting surface (12). Electrodes (27, 28) are disposed external to the lamp body for producing radio frequency energy exciting the gas. A heat resistant glass plate (20) seals the concave lamp body (11). A frit seal (23) can be used for forming a pressure and temperature resistant seal between the concave lamp body (11) and the glass plate (20). The light beam generated by the plasma exists through the glass plate (20).

Abstract: A high efficiency lamp apparatus for producing a light beam of polarized light includes an electrodeless lamp body that defines a chamber. A gas is contained within the chamber such as sulfur or selenium or a compound thereof that can be excited to form a plasma. Electrodes are positioned externally of the lamp chamber for producing radio frequency energy that excites the gas, forming a plasma light source of intense heat that emits a light beam. Electrodes are not subjected to the intense heat generated by the plasma as they are placed externally of the lamp body. A reflector is positioned next to the lamp body for redirecting some of the light emitted by the light source back to the lamp using the reflector so that the lamp reabsorbs light energy to intensify the light source. The reflector includes a polarizing filter that is positioned to receive and polarize the light beam. An insulator prevents heat intensity of the plasma from damaging the polarizing filter as it has a low operating temperature range.

Abstract: A lamp apparatus includes an electrodeless bulb that includes a chamber, a gas contained within the chamber in the bulb, and at least one reflector electrode adjacent the bulb for transmitting radio-frequency electromagnetic energy to the gas in the bulb to excite the gas and cause it to radiate light and for reflecting the light radiated from the bulb. Preferably, there are two reflectors electrodes. The bulb can advantageously be made of a tube, in which case the reflectors electrodes can be made shorter than the bulb and centered thereon so that the intense heat caused by the plasma when the gas is excited does not reach the ends of the bulb.

Abstract: An electrodeless lamp apparatus of high efficiency employs a reflection system that allows the lamp to reabsorb light energy. The energy is redirected back to the light to provide increased system efficiency. The redirected light is of the wrong polarization and/or wrong parts of the color spectrum. The lamp efficiency is increased because of the optical pumping as well as the reuse (after some downshifting) of the returned light. In one embodiment, a projection system provides an image source or projection engine that includes the improved high efficiency lamp of the present invention.

Abstract: Light sources include an electrodeless bulb having an interior, a fill contained within the interior of the bulb, an excitation structure that transmits electromagnetic energy to the fill in the bulb, and cooling fins extending radically outward from the bulb. The fill is excited by the electromagnetic energy to a plasma state that causes light emission and generates heat energy. The cooling fins, when rotated, draw air toward the bulb to cool the bulb. Alternatively, cooling may be provided by a rotatable squirrel cage about an electrodeless bulb. The light sources can be used in display systems, such as field sequential color systems.