Abstract: A technology to automatically control the biasing of an optical duobinary transmitter using a single-drive LN-MZ modulator is provided. A low-frequency signal is amplitude modulated onto a voltage signal input into a Mach-Zehnder optical modulator 22. The optical output from the optical modulator 22 is detected by an optical detection subsystem 30. In a bias control subsystem 40, the low-frequency signal component amplitude modulated onto the electrical signal is detected from the optical output, and a DC bias voltage applied to the optical modulator is controlled such that the low-frequency signal component is either minimized or maximized.

Abstract: A technology to automatically control the biasing of an optical duobinary transmitter using a single-drive LN-MZ modulator is provided. A low-frequency signal is amplitude modulated onto a voltage signal input into a Mach-Zehnder optical modulator 22. The optical output from the optical modulator 22 is detected by an optical detection subsystem 30. In a bias control subsystem 40, the low-frequency signal component amplitude modulated onto the electrical signal is detected from the optical output, and a DC bias voltage applied to the optical modulator is controlled such that the low-frequency signal component is either minimized or maximized.

Abstract: In the application of the optical transmitter to any system for the compensation of passing degradation, the invention provides the optical transmitter which maintains constant modulator output and the highly reliable optical transmission by tuning, the alpha parameter for given systems. As the optical element back-face output power detected by PD6 depends on the optical element driving current amount, the electronic absorption amount of the EA optical modulator monitored by the electronic absorption monitor depends on the optical output of the optical element 5 and the EA optical modulator driving point of the driving part 8. It is possible to detect a change in the driving point in the EA optical modulator by taking a difference between the amount monitored by the PD 6 and the amount monitored by the electronic absorption monitor.

Abstract: There is provided an angular and positional deviation adjusting mechanism of a robot hand comprising a holder secured to an arm, an eccentricity accommodating member urged against the holder by a first spring, and an angular deviation accommodating member biased toward the eccentricity accommodating member by a second spring, a slide member being interposed between the first spring and eccentricity accommodating member to permit sliding of said eccentricity accommodating member, the contact sections of the angular deviation accommodating member and eccentricity accommodating member being formed such as to permit swinging of the angular deviation accommodating member, the biasing force of the first spring belt set to be lower than the biasing force of the second spring.

Abstract: In a robot machine, a hand is rotatably mounted on one end of an arm. The hand is provided with two sets of grasping units each including a pair of opposed fingers which are used to grasp or release an article, for example, a workpiece to be machined by a machine tool. A piston-cylinder assembly is provided for rotating the hand through a ninety degree angle.