Analysis on the characteristics of the speckle field undersharper focusing condition

2021 ◽  
Author(s):  
Chunlin Yang
Keyword(s):  
Speckle Field

scholarly journals Integrated Double-Sided Random Microlens Array Used for Laser Beam Homogenization

Micromachines ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 673
Author(s):  
Wei Yuan ◽  
Cheng Xu ◽  
Li Xue ◽  
Hui Pang ◽  
Axiu Cao ◽  
...  
Keyword(s):  
Laser Beam ◽  
Microlens Array ◽  
Energy Utilization ◽  
Utilization Rate ◽  
Periodic Lattice ◽  
Lattice Distribution ◽  
Speckle Field ◽  
High Laser ◽  
Alignment Problem ◽  
In Series

Double microlens arrays (MLAs) in series can be used to divide and superpose laser beam so as to achieve a homogenized spot. However, for laser beam homogenization with high coherence, the periodic lattice distribution in the homogenized spot will be generated due to the periodicity of the traditional MLA, which greatly reduces the uniformity of the homogenized spot. To solve this problem, a monolithic and highly integrated double-sided random microlens array (D-rMLA) is proposed for the purpose of achieving laser beam homogenization. The periodicity of the MLA is disturbed by the closely arranged microlens structures with random apertures. And the random speckle field is achieved to improve the uniformity of the homogenized spot by the superposition of the divided sub-beams. In addition, the double-sided exposure technique is proposed to prepare the rMLA on both sides of the same substrate with high precision alignment to form an integrated D-rMLA structure, which avoids the strict alignment problem in the installation process of traditional discrete MLAs. Then the laser beam homogenization experiments have been carried out by using the prepared D-rMLA structure. The laser beam homogenized spots of different wavelengths have been tested, including the wavelengths of 650 nm (R), 532 nm (G), and 405 nm (B). The experimental results show that the uniformity of the RGB homogenized spots is about 91%, 89%, and 90%. And the energy utilization rate is about 89%, 87%, 86%, respectively. Hence, the prepared structure has high laser beam homogenization ability and energy utilization rate, which is suitable for wide wavelength regime.

Optical temperature sensor using speckle field

2014 ◽  
Vol 216 ◽  
pp. 312-317 ◽  
Author(s):  
V. Trivedi ◽  
S. Mahajan ◽  
V. Chhaniwal ◽  
Z. Zalevsky ◽  
B. Javidi ◽  
...  
Keyword(s):  
Temperature Sensor ◽  
Speckle Field ◽  
Optical Temperature Sensor

Measurement of curvature radius using phase retrieval with volume speckle field

2010 ◽  
Author(s):  
Mingguang Shan ◽  
Pei Zhi ◽  
Zhi Zhong ◽  
Bo Zhu
Keyword(s):  
Phase Retrieval ◽  
Curvature Radius ◽  
Speckle Field

Study on Properties of Speckle Field Formed by Laguerre-Gaussian Beam Illumination

2015 ◽  
Vol 35 (7) ◽  
pp. 0726001
Author(s):  
李新忠 Li Xinzhong ◽  
田晓敏 Tian Xiaomin ◽  
王辉 Wang Hui ◽  
汤洁 Tang Jie ◽  
王屹山 Wang Yishan ◽  
...  
Keyword(s):  
Gaussian Beam ◽  
Speckle Field

Use of skew rays in multimode fibers to generate speckle field with nonzero vorticity

1999 ◽  
Vol 24 (7) ◽  
pp. 433 ◽  
Author(s):  
M. A. Bolshtyansky ◽  
A. Yu. Savchenko ◽  
B. Ya. Zel’dovich
Keyword(s):  
Speckle Field ◽  
Multimode Fibers

Measurement of eye aberrations in a speckle field

2001 ◽  
Vol 31 (12) ◽  
pp. 1108-1112 ◽  
Author(s):  
A V Larichev ◽  
P V Ivanov ◽  
N G Iroshnikov ◽  
V I Shmalgauzen
Keyword(s):  
Speckle Field

Spatial diffusion of atoms cooled in a speckle field

2000 ◽  
Vol 49 (4) ◽  
pp. 424-430 ◽  
Author(s):  
G Grynberg ◽  
P Horak ◽  
C Mennerat-Robilliard
Keyword(s):  
Spatial Diffusion ◽  
Speckle Field
Sign in / Sign up

Export Citation Format

Share Document