Intermodulation spatial-bandwidth-reduction method in offset-reference holography
Abstract
A method to reduce the recording restrictions in offset-reference holography, i.e., the relaxation of the interrelation between the minimum reference angle and the maximum object width, is presented. After the conventional hologram is recorded, the phase of the half-object illumination is changed by 180 deg, so that one-half of the object is illuminated with a phase 180 deg different than the other part; next, the undeveloped hologram is exposed to the modified object beam, shielding out the reference beam. By this method, we halve the spatial-frequency range of the hologram intermodulation that produces the flare light in the reconstruction, and make the maximum object width in the beam-separation direction 4/3 times as large as in the usual holographic-recording method. This effect leads to 4/3 times as many resolvable object points in the reconstruction of the hologram as in conventional holography.
- Publication:
-
Journal of the Optical Society of America (1917-1983)
- Pub Date:
- September 1975
- DOI:
- 10.1364/JOSA.65.001007
- Bibcode:
- 1975JOSA...65.1007Y
- Keywords:
-
- Bandwidth;
- Fourier Transformation;
- Holography;
- Intermodulation;
- Photographic Recording;
- Wave Front Reconstruction;
- Information Theory;
- Resolution;
- Signal Processing;
- Spatial Filtering;
- Instrumentation and Photography