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Zhaogu Cheng

Publications and source records attributed to Zhaogu Cheng.

2 recordsLinked to original sources

Self-adaptive optical systems for long-distance flying optics.

The focusing characteristics of long-distance flying optics were studied systemically for TEM(mn) Gaussian beams. The results show that the ABCD law of parameter q can be extended to Gaussian modes of any order when waist radius w in the imaginary part of parameter q is replaced by Rayleigh range Z(R) of a certain resonator in the equation. The difference between the real focal length and the geometric focal length, defined as Df, was calculated for laser applications. A novel self-adaptive optical system was demonstrated for precisely controlling the focusing characteristics of long-distance flying optics. Theoretical analyses and experimental results were consistent.

Journal Article↗

Study of a dual-frequency laser interferometer with unique optical subdivision techniques.

A dual-frequency laser interferometer has been developed based on a low-performance commercial interferometer. An optical resolution of 1.24 nm and a nanometer-scale accuracy have been achieved by using unique techniques to obtain an optical subdivision factor of 1/8. A method for reducing static positioning errors was also shown. The measurement of a free-falling body was performed to test the maximum achievable target velocity of the device. The experimental setup for measuring the static positioning errors was also given. The new interferometer could be widely used in nanometer-scale fabrications and measurements.

Journal Article↗