- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Color tuning in Cu(In,Ga)Se <sub/>2</sub> thin-film solar cells by controlling optical interference in transparent front layers
摘要： Aesthetic factors such as colorization in harmony with the surrounding environment are becoming important in the field of applied photovoltaics. Therefore, there exists a need to realize colors in solar cells, with minimum additional cost and efficiency loss. We tuned the color of Cu(In,Ga)Se2 thin-film solar cells by controlling the optical interference between the sputtered Zn(O,S) buffer layer and indium tin oxide (ITO) transparent electrode layer, which are intrinsic components of the solar cell device, without any additional process and/or material. The nontoxic Cd-free buffer layer was prepared in consideration of the environmental factor. In order to minimize the degradation of the photovoltaic performance of the solar cell, the experiment was conducted within the thickness (optical path length) of the Zn(O,S) and ITO transparent front layers, which affected the solar cell performance more optically and less electrically. As the antireflection coating thickness increased, the solar cell was calculated to have a wider color range, lower luminosity, and lower JSC loss. Relatively even efficiencies were obtained with a wide color range.
关键词： color,transparent front layer,optical interference,CIGS thin-film solar cell,nontoxic Cd-free buffer
更新于2025-09-23 15:21:01
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Color image encryption based on enhanced optical interference with different diffraction distances and linear phase color-blend
摘要： We develop a novel method to encrypt a color image by combining enhanced optical interference with phase retrieval algorithm (PRA) and linear phase color-blend (LPCB). In this method, the original color image is encoded into three phase only masks (POMs) with different Fresnel diffraction distances and one fixed random phase mask (RPM). For the decryption in an optical interference system, the three individual POMs are placed in the red, green and blue channels, respectively, and the RPM is placed in the public channel. Only if the right POMs and RPM are fixed their positions properly, one could achieve the expected information. Compared with traditional interference-based color image method, our method eliminates the silhouette problem fully. LPCB is also introduced to modulate the phase value of each pixel of the three POMs to further enhance the security. Numerical simulation results are presented to illustrate the feasibility and effectiveness of the proposed scheme.
关键词： Optical interference,Linear phase color-blend,Phase retrieval algorithm,Color image encryption
更新于2025-09-23 15:21:01
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Demodulation Technique Based on Laser Interference for Weak Photo-Acoustic Signals on Water Surface
摘要： To detect underwater sound-generating targets, a water surface acoustic wave laser interference and signal demodulation technique is proposed in this paper. The underlying principle of this technique involves casting a laser beam onto the water surface disturbed by an underwater acoustic source and creating interference between lights re?ected by the surface and reference lights. A data acquisition and processing system was employed to obtain water surface acoustic wave information from the interference signals by means of demodulation, thus allowing detection of the underwater target. For the purpose of this study, an interference detection platform was set up in an optical dark chamber. High-frequency water surface ?uctuations were introduced in the reference optical path as the phase generated carriers to create laser interference signals in two different paths, which received demodulation based on an improved arc tangent demodulation algorithm and characteristic ratio algorithm, respectively, in view of their different frequencies. Water surface wave information was then derived from such low-frequency and high-frequency signals. According to test results, in the frequency range of 200 Hz–10 kHz, the frequency detection accuracy was better than 1 Hz. The amplitude measurements exhibited high repeatability, with a standard deviation lower than 2.5 nm. The theory proposed in this paper is therefore experimentally veri?ed with good results.
关键词： optical interference,phase generated carrier,water surface acoustic waves,phase demodulation
更新于2025-09-23 15:19:57
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Efficiency Limit of Colloidal Quantum Dot Solar Cells: Effect of Optical Interference on Active Layer Absorption
摘要： Recently, colloidal quantum dot (CQD) solar cells have drawn intense attention because of their accessibility in low-energy solar photons with a facile tunability in electrical properties and their promising feature to go beyond the classic Shockley?Queisser limit of solar cells. Currently, state-of-the-art performance lead sulfide CQD thin-film-based solar cells have a PCE of approximately 12% with large room for improvement. To overcome current limitations on efficiency enhancement in CQD thin-film solar cells, the active layer thickness must increase first by improving carrier transport and formation of band bending to improve collection of carriers. We must note, however, in this heterojunction architecture, estimated optimal active layer thickness has to be revisited considering the interference effect. Specifically, the large refractive index difference between the PbS CQD layer and the ZnO layers account for a significant Fresnel reflection and optical interference in PbS CQD solar cells. This interference effect on high-performing PbS CQD solar cells may not only reduce the effective light absorption but also lead to underestimating the optimal active layer thickness.
关键词： colloidal quantum dot solar cells,optical interference,efficiency limit,active layer absorption
更新于2025-09-12 10:27:22
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[IEEE 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Munich, Germany (2019.6.23-2019.6.27)] 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Ge/YbF <sub/>3</sub> and ZnS/YbF <sub/>3</sub> Thin-Film Combinations Open New Perspectives in Production of Broadband Optics for Mid-Infrared Laser Applications
摘要： Recently, the mid-infrared (MIR) spectral region has become more and more interesting for bio-medical laser applications since large organic molecules exhibit their fundamental vibrational and rotational modes in this range[1]. In this rapidly developing research area, high-quality optical interference coatings are highly demanded. In many laser systems (see, for instance [2]), it is required to separate initial high-power near-infrared beams originated from a driving laser from lower power MIR components emerged in a nonlinear crystal through a nonlinear process (for example, frequency difference generation). The corresponding multilayer dichroic filters reflecting the radiation in the near-infrared range and transmitting the MIR radiation are required. The coatings exhibit desired reflectance and phase in a near-infrared range and high transmittance in a required MIR region. The acceptable levels of reflectance and transmittance, width of the high-reflectance and high-transmittance ranges, polarization states as well as the angle of incidence are dependent on the laser setup. Along with the specified spectral performance, non-optical properties such as good adhesion, low mechanical stress, thermal stability, are of outmost importance. Low stress is crucial in order not to deform the laser beam wave front of the entire laser system and to avoid thermal lensing. Therefore, the choice of the appropriate evaporation materials and optimization of the high-vacuum deposition processes on the one hand and selection of optimal design solutions on the other hand are key elements in development of advanced multilayer optics for laser systems.
关键词： laser applications,dichroic filters,Ge/YbF3,ZnS/YbF3,optical interference coatings,mid-infrared
更新于2025-09-11 14:15:04