During the design process of Blu-ray disc optical pick-up （BD OPU）, the optical system and the collimator lens design is especially important. This paper designs an optical system and some lenses for＇the BD OPU, in...During the design process of Blu-ray disc optical pick-up （BD OPU）, the optical system and the collimator lens design is especially important. This paper designs an optical system and some lenses for＇the BD OPU, including collimator lens, beam shaping lens for laser beam shaping, and cylinder lens for signal detecting. In this OPU, we use a triplet lens to collimate the laser beam. At the same time, we build a series of assembly jigs to make sure that each lens can be put into the OPU basement properly. At last, we get the reading spot image and S-curve photo of OPU, which can be used to read Blu-ray disc （BD）.展开更多
We report a laser writing system for fabrication of diffractive optical elements with He-Cd laser. The wavelength of the light source is 441.6 nm. The output beam is collimated into parallel light with uniform intensi...We report a laser writing system for fabrication of diffractive optical elements with He-Cd laser. The wavelength of the light source is 441.6 nm. The output beam is collimated into parallel light with uniform intensity distribution after passing through the spatial filter with a pinhole of 25μm and the collimating device. A microscopy objective lens with numerical aperture (NA) of 0.65 is used to focus the beam into a small diffraction spot. Any pattern can be written with this system. Experimental results are presented. The written gratings and the phase patterns were verified with a conventional optical microscopy and the Taylor Hobson equipment.展开更多
A static-mode synthetic aperture imaging ladar （SAIL） in which the target and carrying platform are kept still during the collection process is proposed and demonstrated. A target point of 0.5 mm× 0.5 mm and a ...A static-mode synthetic aperture imaging ladar （SAIL） in which the target and carrying platform are kept still during the collection process is proposed and demonstrated. A target point of 0.5 mm× 0.5 mm and a two-di- mensional （2D） object are reconstructed in the experiments, in which an optical collimator with a focal length of 10 m is used to simulate the far-field condition. The achieved imaging resolution is in agreement with the theo- retical design. The static-mode down-looking SAIL has the capability to eliminate the influence from the atmos- pheric turbulence and can be conveniently operated outdoors.展开更多
We present a tabletop-scale spotlight-mode down-looking synthetic aperture imaging ladar （DL SAIL） demon- strator, which is performed by a collimator with 10 m focal length to simulate the far-field optical field. A...We present a tabletop-scale spotlight-mode down-looking synthetic aperture imaging ladar （DL SAIL） demon- strator, which is performed by a collimator with 10 m focal length to simulate the far-field optical field. A specular-point target and a diffuse-reflection target have been used for resolution analysis and 2D imaging, respectively. The experimental result is in agreement with the theoretical design. The experiment setup is capable of simulating a real application scenario for further study. This Letter is focused on the proposition and implementation of spotlight-mode DL SAIL.展开更多
基金the project cooperated by Optical Memory National Engineering Research Center,Tsinghua University and Philips Investment Co.,Ltd.
文摘During the design process of Blu-ray disc optical pick-up （BD OPU）, the optical system and the collimator lens design is especially important. This paper designs an optical system and some lenses for＇the BD OPU, including collimator lens, beam shaping lens for laser beam shaping, and cylinder lens for signal detecting. In this OPU, we use a triplet lens to collimate the laser beam. At the same time, we build a series of assembly jigs to make sure that each lens can be put into the OPU basement properly. At last, we get the reading spot image and S-curve photo of OPU, which can be used to read Blu-ray disc （BD）.
基金This work was supported by the National Outstanding Youth Foundation of China under Grant No.60125512and Program of Shanghai Subject Chief Scientist under Grant No.XD14005
文摘We report a laser writing system for fabrication of diffractive optical elements with He-Cd laser. The wavelength of the light source is 441.6 nm. The output beam is collimated into parallel light with uniform intensity distribution after passing through the spatial filter with a pinhole of 25μm and the collimating device. A microscopy objective lens with numerical aperture (NA) of 0.65 is used to focus the beam into a small diffraction spot. Any pattern can be written with this system. Experimental results are presented. The written gratings and the phase patterns were verified with a conventional optical microscopy and the Taylor Hobson equipment.
基金supported by the National Nature Science Foundation of China(Grant Nos.61275110 and 61108069)the Key Laboratory of Space Laser Communication and Detection Technology of the Chinese Academy of Sciences
文摘A static-mode synthetic aperture imaging ladar （SAIL） in which the target and carrying platform are kept still during the collection process is proposed and demonstrated. A target point of 0.5 mm× 0.5 mm and a two-di- mensional （2D） object are reconstructed in the experiments, in which an optical collimator with a focal length of 10 m is used to simulate the far-field condition. The achieved imaging resolution is in agreement with the theo- retical design. The static-mode down-looking SAIL has the capability to eliminate the influence from the atmos- pheric turbulence and can be conveniently operated outdoors.
基金supported by the National Natural Science Foundation of China(Nos.61275110 and 61108069)the Key Laboratory of Space Laser Communication and Detection Technology of the Chinese Academy of Sciences
文摘We present a tabletop-scale spotlight-mode down-looking synthetic aperture imaging ladar （DL SAIL） demon- strator, which is performed by a collimator with 10 m focal length to simulate the far-field optical field. A specular-point target and a diffuse-reflection target have been used for resolution analysis and 2D imaging, respectively. The experimental result is in agreement with the theoretical design. The experiment setup is capable of simulating a real application scenario for further study. This Letter is focused on the proposition and implementation of spotlight-mode DL SAIL.
