To decrease the performance difference between the actual microscanning thermal imager and the theoretical value, a germanium lens （placed at a certain angle between the infrared focal plane array and infrared lens）...To decrease the performance difference between the actual microscanning thermal imager and the theoretical value, a germanium lens （placed at a certain angle between the infrared focal plane array and infrared lens） dip angle model of flat optical component microscanning is introduced in this letter. The model is the basis for choosing the dip angle of the germanium lens, which is used in the microscanning thermal imager. In addition, the actual dip angle of the germanium lens is chosen according to the model, the infrared lens parameters of the thermal imager, and the germanium lens parameters of manufacture and installation. Only in this manner can the optimal performance of the microscanning thermal imager based on the flat optical component be obtained. Results of the experiments confirm the accuracy of the conclusions above.展开更多
A novel numerical algorithm is proposed to reconstruct the Laplacian of an object field from one single in-line hologram. This method uses two different reconstruction distances of z and z ＋ Δz, or two different rec...A novel numerical algorithm is proposed to reconstruct the Laplacian of an object field from one single in-line hologram. This method uses two different reconstruction distances of z and z ＋ Δz, or two different reconstruction wavelengths of Δ and Δ＋Δλ to reconstruct one digital in-line hologram. Theoretical analysis shows that when the value of Δz or Δλ is sufficiently small, the difference of the two reconstructed fields is an approximation to the second-order Laplacian differentiation of the object wave, and the zero-order and ＂twin-image＂ noise can be almost eliminated simultaneously. Computer numerical simulations and optical experiments are carried out to validate the effectiveness of this algorithm.展开更多
基金supported by the National Defense Pre-Research Fund of China (No. 40405050303)the NationalNatural Science Foundation of Jiangsu, China (No.BK2008049)the NUST Research Funding (No.2010ZDJH12)
文摘To decrease the performance difference between the actual microscanning thermal imager and the theoretical value, a germanium lens （placed at a certain angle between the infrared focal plane array and infrared lens） dip angle model of flat optical component microscanning is introduced in this letter. The model is the basis for choosing the dip angle of the germanium lens, which is used in the microscanning thermal imager. In addition, the actual dip angle of the germanium lens is chosen according to the model, the infrared lens parameters of the thermal imager, and the germanium lens parameters of manufacture and installation. Only in this manner can the optimal performance of the microscanning thermal imager based on the flat optical component be obtained. Results of the experiments confirm the accuracy of the conclusions above.
文摘A novel numerical algorithm is proposed to reconstruct the Laplacian of an object field from one single in-line hologram. This method uses two different reconstruction distances of z and z ＋ Δz, or two different reconstruction wavelengths of Δ and Δ＋Δλ to reconstruct one digital in-line hologram. Theoretical analysis shows that when the value of Δz or Δλ is sufficiently small, the difference of the two reconstructed fields is an approximation to the second-order Laplacian differentiation of the object wave, and the zero-order and ＂twin-image＂ noise can be almost eliminated simultaneously. Computer numerical simulations and optical experiments are carried out to validate the effectiveness of this algorithm.
