Abstract: An optical signal detector is provided that detects an optical signal from an optical source using a plurality of optical sensors having different wavelength selectivities, thereby determining the peak wavelength of the optical signal and measuring the power of an optical signal corresponding to the peak wavelength. According to the optical signal detector, separate optical filters are not required and space and costs attributable to the installation of the optical filters can be saved, and thus there are effects in that the overall size and manufacturing costs of the device can be reduced.

Abstract: The present invention relates to an optical power and extinction ratio controlling device and method. An optical signal output from a light source is detected and optical power and extinction ratio of the light source are controlled. In detail, a feedback signal is provided to the light source to automatically control the bias current based on a DC signal output by a photodetector detecting the optical signal. Therefore, the optical output of the light source is maintained. Also, an optical signal output by the photodetector is converted into a predetermined times DC signal, and a feedback signal is provided to the light source to automatically control the modulation current based on the DC signal. Therefore, the extinction ratio of the light source is maintained. As a result, the extinction ratio is automatically maintained to satisfy the change of condition and the characteristic of light source, thereby maintaining quality optical outputs.

Abstract: The present invention relates to a light wavelength and intensity measuring device. The device automatically measures a center wavelength of the light source and an intensity of the light corresponding to the center wavelength by using a main photodetector, at least one optical filter, and at least one sub photodetector when the light source is connected to the device. The main photodetector detects the intensity of the light applied by the light source, the optical filter transmits the light corresponding to a prediscriminated transmission wavelength, and the sub photodetector detects the intensity of the light transmitted through the optical filter. Therefore, the light intensity is more accurately measured by calibrating the intensity according to the wavelength.

Abstract: The present invention relates to an optical power and extinction ratio controlling device and method. An optical signal output from a light source is detected and optical power and extinction ratio of the light source are controlled. In detail, a feedback signal is provided to the light source to automatically control the bias current based on a DC signal output by a photodetector detecting the optical signal. Therefore, the optical output of the light source is maintained. Also, an optical signal output by the photodetector is converted into a predetermined times DC signal, and a feedback signal is provided to the light source to automatically control the modulation current based on the DC signal. Therefore, the extinction ratio of the light source is maintained. As a result, the extinction ratio is automatically maintained to satisfy the change of condition and the characteristic of light source, thereby maintaining quality optical outputs.