New Method for All Movable Zoom Lens Design

Wei, 蔡伟 Cai; Ying, 张鹰 Zhang; Xin, 张鑫 Zhang; Yanxiong, 伍雁雄 Wu; Jizhen, 张继真 Zhang

doi:10.3788/aos201232.0322008

Cited by 3 publications

(1 citation statement)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Evaluation result can be illustrated by this figure. An important problem of traditional methods is that the weighted average holds all indexes are linearly dependent [8][9], and among evaluation dimensions, substitution exists.…”

Section: Evaluation Of Knowledge Learning Based On Radar Chartmentioning

confidence: 99%

Evaluation of Team Learning in Expressway Projects

Zhang

Han

Chen

2011

AMR

View full text Add to dashboard Cite

Four factors which are connected with effectiveness of team learning were defined, and they were motivation of knowledge learning, ability of knowledge transfer and sharing, methods of knowledge learning and system of knowledge learning respectively. Evaluation model of team learning in expressway project was established. Based on this model, weights and values of each secondary level index were determined with Delphi method. Using the weighted average method, evaluation values of four first level indexes were calculated, which were drawn in radar chart. In order to seek the worst result, radar chart should be adjusted, and final evaluation result of knowledge learning was ascertained by calculating the minimum area of polygon. Taking YR expressway project as an example for positive analysis, evaluation and result analysis of team learning was carried out.

show abstract

Section: Evaluation Of Knowledge Learning Based On Radar Chartmentioning

confidence: 99%

Evaluation of Team Learning in Expressway Projects

Zhang

Han

Chen

2011

AMR

View full text Add to dashboard Cite

show abstract

Design of an optical passive semi-athermalization zoom lens

Yan,

Chen,

et al. 2024

Appl. Opt.

View full text Add to dashboard Cite

Traditional zoom lenses cannot clearly image during the entire zoom process when the ambient temperature changes and needs to focus frequently at middle focal length positions. An innovative design method called the optical passive semi-athermalization (OPSA) design for zoom optical systems is proposed which, based on the difference in the focusing sensitivity of the focusing group at short and long focal length positions, seeks out sensitive groups that have a greater impact on the imaging quality at the short focal position. By changing the temperature characteristics of the temperature-sensitive lenses in these groups, an OPSA zoom optical system can be realized, which exhibits a compact structure and excellent imaging quality. Under the ambient temperature of −40∘C to +60∘C, the OPSA zoom lens needs to refocus only once at the long focal length position, which can ensure an image clearly during the entire zoom process. Remarkably, this innovative method not only mitigates the frequent focusing challenges in traditional zoom lenses, but also contributes to the diminutive size.

show abstract

基于Alvarez透镜的紧凑型红外连续变倍系统设计

Ouyang Qi,

Liu Mengyao,

Ning Yan

et al. 2024

激光与光电子学进展

View full text Add to dashboard Cite

In this study, a transverse moving infrared optical continuous zoom system based on the Alvarez lens is proposed to address the challenges associated with the complex structure and large volume of traditional axialmoving mechanical optical zoom systems. The system consists of two sets of Alvarez lenses, apertures, focusing lenses, and infrared detectors. Herein, two sets of Alvarez lenses adopt a Keplertype telescope structure, where the first set of Alvarez lenses functions as the zoom group and the second set of Alvarez lenses serves as the compensation group. The infinitely far incident light passes through two sets of Alvarez lenses and exits, the emitted parallel light is then focused and imaged onto the target surface of the infrared detector through a fixed focal lens. Utilizing Zemax software for optical simulation, our designed optical zoom system covers the 8-12 μm long wave infrared band, with a maximum field of view angle of 6°, a maximum pupil diameter of 6 mm, an Fnumber of 2, distortion of <2. 1%, and a total optical length of ~74 mm. The Alvarez lens only requires to be horizontally moved by ~1 mm to achieve continuous optical magnification from 5× to 15× . Moreover, the modulation transfer function of the proposed optical zoom system can attain up to 0. 5@17 lp/mm, assuming a resolution of 320×240 and pixel sizes of 30 μm for the infrared detector. The simulation results indicate that the system has the advantages of high magnification, a compact structure, and high imaging quality, making it a promising candidate for applications in the field of miniaturized infrared zoom imaging.

show abstract

New Method for All Movable Zoom Lens Design

Cited by 3 publications

References 0 publications

Evaluation of Team Learning in Expressway Projects

Evaluation of Team Learning in Expressway Projects

Design of an optical passive semi-athermalization zoom lens

基于Alvarez透镜的紧凑型红外连续变倍系统设计

Contact Info

Product

Resources

About