RESUMO
State-of-the-art autostereoscopic displays often do not comply with mandatory requirements for outdoor use, because of their limitations in size, luminance, number of 3D viewing zones, and maximum 3D viewing distances. In this paper we propose a concept for a modular autostereoscopic multi-view laser display with sunlight readable luminance, theoretically up to several thousand 3D viewing zones, and maximum 3D viewing distances of up to 70 meters. Each picture element contains three laser diodes, a cylindrical microlens, as well as a MEMS mirror, which deflects the collimated light beams to the left and right eyes of multiple viewers in a time-multiplexed manner. To demonstrate the principle, we have developed a prototype display with 5 x 3 picture elements.
RESUMO
A new method based on an optical delay line structure is proposed for two-dimensional raster optical beam steering. For one-dimensional beam steering, the laser beam to be deflected is split into N co-directional sub-beams of equal intensity with the aid of a plane-parallel plate. These sub-beams experience a relative time delay, which translates into a phase difference, thus forming a phased array. When the laser wavelength is tuned, the relative phase varies and the far-field interference footprint can be steered across a receive plane. By employing two plane-parallel plates in series, the described scheme can be extended to produce a two-dimensional N x N array of sub-beams, allowing two-dimensional beam steering via wavelength tuning. In this case, wavelength tuning over a larger range leads to a linear deflection which repeats itself in a raster-like fashion. One direction of deflection repeats itself multiple times as wavelength is scanned over larger range, that is, a raster effect. In this paper, the principle is theoretically derived and formulated, and the preliminary experimental results with four sub-beams are presented.