Absorption holograms made with mode-stabilized laser diodes for use in a satellite communications link

An experimental technique is presented for constructing absorption holograms in IR-sensitive material with mode-stabilized laser diodes. The combination of an extremely sensitive recording medium and high power available from the diode is exploited to permit minimum exposure times. This prevents the inherent modal instability of the laser diode from becoming a problem while the interference pattern is recorded. Diffraction efficiencies into the first order were measured to be greater than 14% for small construction angles, indicating some phase effects. These absorption holograms will be used as the first step in a two-step process to produce holographic optical elements for use with laser diodes in a satellite communications link.