Holography has been widely applied in industry measurement, especially in 3D non-contact testing. Combining a high
resolution charge-coupled device (CCD) with a phase modulating liquid crystal display (LCD), holographic interferogram recording and display could be realized by digital holographic technique. Digital holographic technique has a great number of important and practical applications. In the conventional holography hologram was detected and
reconstructed by the holography panchromatic plate, or the photoconductive thermoplastic film, or the BSO crystal and
etc. But in the digital holography--the numerical version of the conventional holographic technique, hologram is
digitally detected by CCD and then displayed on the computer monitor. By reconstruction, the hologram is writted into
LCD, then illuminating the LCD with the reference wave, the tested object may be reconstructed optically. In this paper
the application technique of CCD/LCD in holography is theoretically studied and the bottle techniques have been solved.
According to the resolving power of the CCD and LCD, the angle between the two interfering waves should be less than
3° for recording the interference fringes with high spatial frequency. The simple and prospective optical architecture is
perhaps Twyman-Green interferometer for easy to adjust the required small angle between reference and tested object
waves, and also optical path deference for satisfying the requirement of spatial and temporal coherence. The
disadvantages of CCD/LCD digital holographic technique is the small separation angle between zero-order and ±1-order
diffraction. In order to separate ±1-order from zero-order diffraction, the minimum fringe spacing formed by the
interference of object wave with reference wave should satisfy the sampling theorem. This decides a relationship
between the size of object and the recording distance, which will be discussed in detail in the following text. And also
discussion about the experimental research of LCD in digital holography would be included in our paper.
Hybrid optoelectronic joint transform correlator is very useful for target detection and recognition in military and
industry field. Nowadays, there are two kinds of usual detectors: one is visible detector which is sensitive to the diffusion
of target; the other is infrared detector which is sensitive to the radiation of target. The performance of these two
detectors both depend on their working conditions.
Designing perfect optical system is the first step to target detection. While the merit of infrared optical system is it can
not only detect great distance but also detect the target in the turbid air or smoke, flog and snow no matter at day or night.
So it is much more appropriate to be applied in cluttered and formidable conditions and it can enhance target recognition
In this paper, the infrared detector we adopted is infrared focal plane arrays with working waveband 8-12μm. Its
resolving power is 30 lp /mm. For the infrared optical system, the effective focal length, relative aperture and the field of
view should be large enough to ensure the long distance and large field of view target can be detected. In hybrid
optoelectronic joint transform correlator, the high performance of infrared telephoto lenses is required. Here, we
designed infrared telephoto lenses composed of three lenses. Its structure is simple but its performance is very good. It
has met the requirement of target detection. Thus we can get the longer detection distance and higher recognition