Industrial Technology Research Institute

Eric G Lean

Der-Ray Huang

Jau-Jiu Ju

Chao-Nien Huang

Ying-Tsung Lu

Chin-Yuan Chen

Ching-Chin Wu

Fei-Chang Hwang

Ming-Huang Hong

This specification discloses a planar optical waveguide DWDM (Dense Wavelength Division Multiplexer), which is an integrated DWDM made by using the planar optical waveguide manufacturing technology. A diffractive grating is used in a planar optical path to direct beams of different wavelengths in a beam into different directions. An arrayed waveguide installed at the output end of the planar optical path couples the beams of different wavelengths to an optical fiber connected at the output end, separating the waves. On the other hand, a preferred embodiment of the invention has an arrayed lens between the diffractive grating and the arrayed waveguide. The arrayed lens can correct the deviated diffractive beams due to thermal deformation of the diffractive grating and conduct them into the arrayed waveguide.

Planar optical waveguide dense wavelength division multiplexer

A white light-emitting diode and a method of fabricating the same diode are disclosed. The white light-emitting diode is fabricated by epitaxy, which can produce two peaks in the spectrum at the P-N junction by appropriately adjusting epitaxial parameters such as temperature, pressure, NH.sub.3 flux and the ratio of H.sub.2 to N.sub.2 or the concentration of dopant, such as Mg or Si. The diode can thus radiate white light by adjusting the wavelength and the intensity of the principal peak in the two peaks. Further, quantum well structure can be formed in the diode. By appropriately adjusting the epitaxial parameters, the spectrum of the quantum well structures may have more than one peak. Therefore, white light can be generated by combining the light with wavelengths at two or three different peaks. The white LED can radiate white light itself and need not involve combining many LEDs, so that the cost and the difficulty of fabricating the white LED lamp can be reduced. Moreover, the white LED can radiate white light itself, and does not need to excite fluorescent material to radiate white light. Accordingly, the lifetime of the white LED lamp is not limited by the relatively short lifetime of fluorescent material.

White light-emitting diode and method of manufacturing the same

A prism-type objective lens is provided for use in the pickup head of an optical disc drive capable of driving two types of optical discs such as a CD and a DVD. The prism-type objective lens allows the pickup head to be made more compact in size with reduced structural complexity, and also allows the pickup head to read data from two different types of optical discs. The prism-type objective lens includes a prism having a cross section substantially in the shape of a right triangle, a front aspherical plano-convex lens, and a rear aspherical plano-convex lens, where the planar surface of each lens is attached to one or the other of the leg sides of the prism. The hypotenuse side of the prism can be formed with two aperture areas where different reflective layers are coated. Alternatively, the hypotenuse side of the prism can be formed with a reflective HOE layer that allows the laser beam incident on it and reflected from it to be diffracted into two beams which are focused at different points. Either manner allows the pickup head to read data from two different types of optical discs.

Prism-type objective lens for the pickup head of an optical disc drive

Growing community of inventors

Hsinchu, Taiwan

Eric G Lean