Abstract: A crank transmission mechanism includes a crank unit having a rail portion connected to an end thereof and a guide member is connected with a shaft which is connected with a disk. The rail portion is movably engaged with the guide member. A transmission unit is connected between the crank unit and the disk, the rail portion and the guide member are connected to the transmission unit. The transmission unit is adjusted according to the relative position between the rail portion of the crank unit and the guide member. The crank transmission mechanism is compact and the torque can be adjusted by slowly adjusting the length of the crank unit. The crank transmission mechanism can be used to bicycles, tricycles and elliptical exercising machine.

Abstract: An auto feedback and photo attenuation structure of a vertical cavity surface emitting laser (VCSEL) includes a VCSEL combined with a monitor photodetector (MPD). The thickness of the absorbing layer of the MPD may be adjusted, so that when output light of different wavelengths passes through the MPD, a portion of light may be absorbed by the absorbing layer to function as a feedback path of an auto power control, and a portion of light may penetrate through the absorbing layer, and may satisfy the requirement of the eye safety class I. The thickness of the absorbing layer of the MPD may be controlled precisely, thereby increasing the quality of products and decreasing cost of fabrication.

Abstract: An auto feedback and photo attenuation structure of a vertical cavity surface emitting laser (VCSEL) includes a VCSEL combined with a monitor photodetector (MPD). The thickness of the absorbing layer of the MPD may be adjusted, so that when output light of different wavelengths passes through the MPD, a portion of light may be absorbed by the absorbing layer to function as a feedback path of an auto power control, and a portion of light may penetrate through the absorbing layer, and may satisfy the requirement of the eye safety class I. The thickness of the absorbing layer of the MPD may be controlled precisely, thereby increasing the quality of products and decreasing cost of fabrication.

Abstract: The present invention is to provide a planar type light emitting and receiving component having a high light gathering efficiency, and including a substrate provided with a epitaxy growth layer and formed with a cavity, an active region provided in the epitaxy growth layer for emitting light, and a light gathering lens formed in the cavity and located close to the active region of the epitaxy growth layer. Thus, the distance between the active region and the light gathering face may be shortened, thereby efficiently gathering the light.