In this work, we investigated the electronic and optical properties of traditional semiconductor materials, InAs and GaSb. By constructing crystal structures for InAs and GaSb, we performed calculations using the first-principles Density Functional Theory (DFT) with the HSE+SOC method. In contrast to the results obtained using the traditional PBE algorithm, which yielded a negative or zero bandgap for InAs, our calculations provided theoretical support and accurately determined the bandgap values of 0.3658 eV for InAs and 0.772 eV for GaSb. These results align well with the experimentally reported bandgap values for the bulk materials. Furthermore, by strictly adhering to the validity conditions of DFT, we obtained accurate optical properties that are consistent with experimental results. Based on the optical characteristics of InAs and GaSb semiconductor materials, it was demonstrated that have a high performance for absorbing light. These findings provide a possibility for using DFT calculations in the development of second-generation InAs/GaSb superlattice infrared detectors.
The microlens array (MLA) scanning system is a relatively new solution for beam scanning, and are used in numerous applications, such as laser radar and optical communications. Excrescent light generated by overlapping divergent beams from adjacent microlenses increases with scanning angle and as a result, the rays do not fill the clear aperture of the MLA. The fill factor is proposed to characterize the fill rate of beams, and its effects on the point spread function (PSF) and modulation transfer function (MTF) are analyzed, this work can benefit the design and evaluation of MLA systems.
Aiming at the problem of obvious diffraction when light encounters small-diameter components during transmission, we analyze the diffraction effect of micro-lens arrays in this paper. Since the fill factor of the micro-lens array determines the amount of light entering the system, which affects the diffraction effect, and ultimately affects the imaging quality together with the diffraction of the small components, we first use the scalar diffraction theory to analyze and establish the mathematical model of the fill factor of the aperture array and propose a theoretical calculation method. According to this method, different forms of aperture arrays with the same fill factor can be given through geometric relations and system parameters, and then we use an optical analysis software VirtualLab to simulate the diffraction effect. By comparing the light intensity distribution forms and exploring the diffraction effect of the aperture array form on the imaging quality, corresponding conclusions are drawn and a more advantageous structural form is selected.
As part of investigating the human perception of polarized light, Haidinger’s brushes (HB) is well-known optical phenomena. Although differences in the human polarization perception were well known there was a limited quantifying to them. This paper presents a 3D Stokes model of the human polarized light perception, views the human perception of polarized light as a multivariable applied optics problem to simulation and explored the optical phenomena of Haidinger’s brushes. The images comparison verifies that the simulation patterns and detected images are consistent which proves the model is appropriate for simulating polarization perception of the human eye. Then this paper explored the optical limitations of perception and macula density. The combination of the 3D Stokes model and experimental verification opens up new possibilities to become an early diagnostic method for eye polarization sensitivity and macular degeneration. The objective is to give purpose and new mathematics understanding to the biomedical optical phenomenon.
We introduce an integrated polarization detection structure consisting of a photoelectric conversion material, silicon (Si), in the form of a wire grid and an aluminum (Al) wire grid polarizer layer. This structure provides transverse magnetic (TM) polarization absorptivity and an enhanced extinction ratio in the visible spectrum. Finite difference time domain simulations were used to examine the influences of different periods and thicknesses of the Si and Al grid components. The results showed that the absorptivity of TM polarization exceeded 70% in the visible spectrum (a 20% improvement), the absorptivity of transverse electric polarization was reduced by >90 % , and the extinction ratio improved by a factor of 33. When the incidence angle is over the range of 0 deg to 30 deg, the absorptivity of TM polarization and the extinction ratio perform well, exceeded 60% and 75.
We propose an optoelectronic measurement system for testing the optical parameters of infrared seeker, such as the position of the image plane, the size of the diffused spot, and the diameter of the scanning circle. The measurement method and operating principle of the optoelectronic measurement system have been introduced. The source of the stray light in the optoelectronic measurement system have been analyzed by using FRED software, and the stray light have been restricted effectively by a co-centered mica plate which closes to the substrate of pinhole. Experimental results show that the test error for the size of the diffused spot is less than ±0.01 mm, the test errors for the position of the image plane and the diameter of the scanning circle are less than ±0.02 mm.
An optical attenuator with special performances, such as wide spectrum, high precision, polarization-independent, and lager dynamic range, is the key device for testing the communicat ion link performance in free-space laser communicat ion systems. We propose a polarizat ion-independent variable optical attenuator based on rhombic prism. Two rhombic prisms are used to balance the polarization aberrat ions, and the incident surfaces of the rhombic prisms are perpendicular to each other. We control the incident angle of the rays, which incident the reflected surfaces of the rhombic prisms, between the Brewster angle and the critical angle, then the attenuation coefficient of the attenuator can be changed. The results of theoretical analysis and numerical simulation show that the designed attenuator is polarization independent, the wavelength range is from 790nm to 1550nm, the dynamic range of attenuation coefficient is from -40 dB to -3 dB, and the wavefront aberration is less than /20@974nm.
With the development of information technological progress, M-Learning and Micro-learning is becoming more and more popular among learners as a new micro-learning resources. Micro-curriculum is playing a more and more important role in daily learning. The students can create a new way of optical course learning through "WeChat". Under the mutual interaction of two or more parties, the use of "WeChat" can fully arouse the students' interest in learning, make the subjective initiative of students, and achieve the ultimate goal of improving the level of students. In this paper, through the analysis of the current situation of college students using the "WeChat", a new teaching model suitable for "optics" teaching is summarized, and the use of "WeChat" has been infiltrated into the teaching process, using science and technology to assist teaching. Students' interest in autonomous learning.
To improve the research quality preparation for graduate study and looking for job competition ability of undergraduates students, the education orientation objective need to be explicit. Universities need develop undergraduates' cultivation plan according to students' classification. Based on analysis of students export characteristic, there will be corresponding cultivation plan.
Keep tracking study during the cultivation plan implantation process, the Curriculum system and related manage documents are revised corresponding to exist problems. There are mainly three kinds of undergraduates' career direction plan for opto-electronic major undergraduates. In addition to the vast majority university graduates opting for direct employment, nearly one third of university students choose to take part in the postgraduate entrance exams and other further education abroad, and also one-tenth choose their own businesses, university chooses are diversified.
The exports are further studying as graduates, working and study abroad. Because national defense students are also recruited, the cultivation plan will be diversified to four types. For students, who go to work directly after graduation, the "Excellence engineers plan" is implemented to enhance their practice ability. For students, who will study further as graduate student, the scientific innovation research ability cultivation is paid more attention to make good foundation for their subsequent development. For students, who want to study abroad after graduation, the bilingual teaching method is introduced, and the English environment is built. We asked foreign professionals to give lectures for students. The knowledge range is extending, and the exchange and cooperation chance is provided at the same time. And the cultivation plan is revised during docking with Universities abroad. For national defense students, combat training and other defense theory courses are added to make them familiar with force knowledge. And with national defense students’ excellence engineer plan, more army practice chance is provided. The students can integrate into army life much faster. The advantages of national defense students are much more highlighted. The graduates can serve motherland better than before. It is shown from the practice process that the revised cultivation plan is suitable for diversified undergraduates. And the education result is improved in a large amount consequently.
The requirements on science and technology graduates are more and higher with modern science progress and society market economy development. Because optical engineering major is with very long practicality, practice should be paid more attention from analysis of optical engineering major and students’ foundation. To play role of practice to a large amount, the practice need be systemic and correlation. It should be combination of foundation and profundity. Modern foundation professional knowledge is studied with traditional optical concept and technology at the same time. Systemic regularity and correlation should be embodied in the contents. Start from basic geometrical optics concept, the optical parameter of optical instrument is analyzed, the optical module is built and ray tracing is completed during geometrical optics practice. With foundation of primary aberration calculation, the optical system is further designed and evaluated during optical design practice course. With the optical model and given instrument functions and requirements, the optical-mechanism is matched. The accuracy is calculated, analyzed and distributed in every motion segment. And the mechanism should guarantee the alignment and adjustment. The optical mechanism is designed during the instrument and element design practice. When the optical and mechanism drawings are completed, the system is ready to be fabricated. Students can complete grinding, polishing and coating process by themselves through optical fabricating practice. With the optical and mechanical elements, the system can be assembled and aligned during the thesis practice. With a set of correlated and logical practices, the students can acquire the whole process knowledge about optical instrument. All details are contained in every practice process. These practical experiences provide students working ability. They do not need much adaption anymore when they go to work after graduation. It is favorable to both student talents and employer.
Shack-Hartman wave sensor is applied widely in wave-front process with real-time and stable advantages. To increase the testing accuracy of Shack-Hartman sensor, the centroid testing accuracy must be increased first. But the centroid testing accuracy is decided by the detector performance, which is at the system focal plane. The testing accuracy will decrease with detector pixel size increasing. Based on micro-scanning system, the detector in Shack-Hartman wave sensor will receive four images of the wave-front under test. They are rebuilt to a single image after digital image procession. The centroid is calculated and wav-front is rebuilt by wave-front processor. The pixel distance is subdivided to 1/N along X and Y direction respectively with micro-scanning system. N*N is the detected image frames. The sub-pixel shifting images are rebuilt to a whole image after digital image procession. And the resolving power is realized to be increased finally. With application of micro-scanning in Shack-Hartman wave sensor, the system error due to detector accuracy in Shack-Hartman will be decreased. Consequently, the requirement on detector will be decreased. The resolving power of detector is improved greatly. As a result, the image quality testing accuracy of Shack-Hartman wave-front is improved. The image quality testing accuracy of traditional Shack-Hartman wave-front sensor will be increased within the original field of view. And the application range of Shack-Hartman wave sensor is also enlarged effectively.
As an important part of machine vision, compound eye optical systems have the characteristics of high resolution and large FOV. By applying the compound eye optical systems to target detection and recognition, the contradiction between large FOV and high resolution in the traditional single aperture optical systems could be solved effectively and also the parallel processing ability of the optical systems could be sufficiently shown. In this paper, the imaging features of the compound eye optical systems are analyzed. After discussing the relationship between the FOV in each subsystem and the contact ratio of the FOV in the whole system, a method to define the FOV of the subsystem is presented. And a compound eye optical system is designed, which is based on the large FOV synthesized of multi-channels. The compound eye optical system consists with a central optical system and array subsystem, in which the array subsystem is used to capture the target. The high resolution image of the target could be achieved by the central optical system. With the advantage of small volume, light weight and rapid response speed, the optical system could detect the objects which are in 3km and FOV of 60°without any scanning device. The objects in the central field 2w=5.1°could be imaged with high resolution so that the objects could be recognized.
Infrared scene simulator is now widely used to simulate infrared scene practicality in the laboratory, which can greatly reduce the research cost of the optical electrical system and offer economical experiment environment. With the advantage of large dynamic range and high spatial resolution, dynamic infrared projection technology, which is the key part of the infrared scene simulator, based on digital micro-mirror device (DMD) has been rapidly developed and widely applied in recent years. In this paper, the principle of the digital micro-mirror device is briefly introduced and the characteristics of the DLP (Digital Light Procession) system based on digital micromirror device (DMD) are analyzed. The projection system worked at 8~12μm with 1024×768 pixel DMD is designed by ZEMAX. The MTF curve is close to the diffraction limited curve and the radius of the spot diagram is smaller than that of the airy disk. The result indicates that the system meets the design requirements.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.