抄録
Our fringe printer for printing digitally synthetic holograms, which we reported in a previous article, was improved to increase its stability and resolution. The old model was capable of printing elliptical dots in a diameter of 2×4 μm by focusing the beam of a laser diode onto a hologram dry plate. However, active control to focus the laser beam was not taken into account in the design, and therefore, the resolution and the stability were limited. The new fringe printer has had mechanisms incorporated to detect surface undulations in the recording materials and control the beam waist only on the surface. These improvements made it possible to reduce the dot size to 1.5×3 μm and to keep the dots size within a large area.
