A process of aligning electro-optical devices that associate a semiconductor, laser diode or electroluminescent component with an optical component, such as an optical fiber. These devices must be aligned with a precision of from .+-.1 to .+-.10.mu.. The semiconductor component is integral with a centering part through the intermediary of a first bracket. The optical component, through the intermediary of a second bracket, is integral with a container in which is placed a hardening material. The centering part is plunged in the hardening material, with three degrees of mobility. The alignment is dynamic. When adjustment has been made, the hardening material is rapidly and rigidly fixed.

A method for bonding a semiconductor laser element, wherein a laser chip (4) is mounted on a stem (1) and a driving electric power is supplied to the laser chip through members for mounting the laser chip so that the laser chip emits a laser light, then the direction of the laser light is examined, and position of the laser chip is adjusted, in a manner that the direction of the laser light becomes within a predetermined range, and subsequently the laser chip is bonded on the pedestal (2) upon detection of entering the direction in the range, by flowing a large current through in the pedestal (2).

A dental retention pin preferably made of metal is provided with a closed, cylindrical coating of bond assisting material, and an additional layer of a plastics filling material in order to obtain a physical-chemical or a purely chemical bond between the retention pin and the filling structure for obtaining a substantially increased retention power compared with known metal pins, which merely result in a mechanical or mechanical-physical joint to the filling structure. The retention force will be increased by shrinking the bond assisting layer or the outermost plastics layer onto said bond assisting layer around the pin so that the layer spans itself around the pin in a ring-like manner. Furthermore, examples for the structure of a retention pin are described, which improve the handling and insertion of such retention pins by the dentist considerably.

A light source device emits light for positional alignment and light for adhesion toward the optical devices. A position detecting device receives the light for positional alignment from the optical devices and optically detects a positional displacement of the optical devices. A positional alignment mechanism moves the optical devices with respect to each other in accordance with a detecting result of the position detecting device, thereby positionally aligning the optical devices. After the optical devices are positionally aligned, the light for adhesion is radiated to a photo-curing adhesive resin interposed between the optical devices, thereby adhering the optical devices.

An adjustable pad assembly is used for aligning a polygon of a laser optical system that is supported by a housing and requires precise alignment with respect to a base for proper operation of the optical system. A plurality of the adjustable pad assemblies are located between the base and the housing. Each pad assembly includes a mounting plate that is positioned on the base of a fixture, and a bushing that is secured to the housing. A compressible ring surrounds a surface on the plate that receives an adhesive. The housing is adjusted relative to the base to align the polygon, and then held stationary until the adhesive cures to bond the mounting plate and bushing together.