Abstract: As edge-emitting semiconductor laser incorporating a narrow waveguide design is disclosed. The narrow waveguide expands the lateral mode size, creates a large modal spot size, and insures higher-order modes are beyond cutoff. Separate current confinement allows the current injection region to match the mode size. The resulting device exhibits single-mode operation with a large spot-size to high output powers.

Abstract: An edge-emitting semiconductor laser incorporating a narrow waveguide design is disclosed. The narrow waveguide expands the lateral mode size, creates a large modal spot size, and insures higher-order modes are beyond cutoff. Separate current confinement allows the current injection region to match the mode size. The resulting device exhibits single-mode operation with a large spot-size to high output powers.

Abstract: A positioning system adapted for use with micromechanical actuators provides feedback control of the position of the movable element of the actuator utilizing a low Q sensing coil. The effective inductance of the sensing coil changes with position of the movable element to change the frequency of oscillation of a variable oscillator. The output of the variable oscillator is compared in a phase detector to a reference oscillator signal. The phase detector provides a pulsed output having a pulse duty cycle related to the phase or frequency difference between the oscillator signals. The output of the phase detector is provided to a drive coil which applies a magnetic force to the movable element which balances the force of a spring. The movable element can be displaced to a new position by changing the frequency of the reference oscillator.