Automated surface mounting of optical elements

In conclusion a fully automated surface mounting assembly procedure has been developed for mounting optical elements. It is based on low cost universal tripod mounts, free space optical interconnection, and on-line adjustment of the elements. It is characterized by submicron mounting precision and excellent mechanical properties. Flexibility in the layout, simple handling, high packaging density render this technique suitable to low cost prototyping and mass production of optoelectronic device

Flexible automated assembly of micro-optical elements (optical SMD)

An automated assembly technique for small optical components has been developed. It concerns components such as, e.g., laser diodes and LEDs, fibers, lenses, beamsplitters, polarizers, mirrors, crystals, prisms, diffractive elements or photodiodes. It is based on the flexible 2-dimensional arrangement of an universal tripod holder (10 x 10 x 4 mm) on a planar mounting plate. Its particular mechanical structure allows to align the optical elements on-line and to attach them to the mounting plate in a one step procedure. The different elements are aligned with an accuracy of +/-1 mu m and attached one after the other. Very good position stability (+/-0,7 mu m, +/-0,2 mad) during the attachment procedure has been achieved by laser point welding. They are optically interconnected by free-space propagation of a light beam with a diameter of up to 8 millimeters. Mass production has been shown with a collimator as test vehicle. The collimator is composed of two elements (laser diode and collimating lens) and is mounted entirely automatically by two co-working robots. Easy prototyping has been shown with the realization of the optical position sensing system featuring a high precision linear magnetic bearing. Flexibility, simple handling, high packaging density and low cost make this new assembly technique suitable to both mass production and protoyping of small opto electronical devices

Accuracy and beam pointing stability of surface mounted optical elements

Considerable efforts are presently being made in the fabrication of miniaturized optical devices. An automated assembly technique for small optical components based on standardized holders and on-line alignment of the optical elements has been developed. This optical surface mounted devices (O-SMD) technique consists of a flexible 2D arrangement of an universal tripod holder on a planar mounting plate. The compliant structure allows to align the optical elements during the mounting process in all 6 degrees of freedom and to attach them to the mounting plate in a one step procedure by laser point welding. The optical elements are interconnected by free-space propagation of the light. Flexibility, simple handling, high packaging density and low cost make this well established assembly technique suitable to both mass production and rapid prototyping of small optoelectronic devices. However, problems were encountered with the assembly of devices requiring very high angular beam precision adjustments. We report on a new improved version of the tripod holder which allows to considerably improve the beam pointing stability of the tripod holder. This allows to extend the field of applications of this technique to optical systems with more stringent angular specifications such as, e.g., spatial beam combiners and long distance free space optical transmission system