| 摘要 |
<p>In an optical positioning system, a holographic optical element having a plurality of rectangular apertures (6, 8, 10) has predetermined ones of its aperture edges castellated or notched (42, 44, 46) in order to null out undesired light energy in target areas. The apertures may be fitted with diffraction grating patterns that may also be castellated for the same purpose. A method of using the apertures and grating pattern castellated holographic optical element is also provided.</p> |
