Pose and Focal Length Estimation Using Two Vanishing Points with Known Camera Position [PDF]
Sensors, 2023 This paper proposes a new pose and focal length estimation method using two vanishing points and a known camera position. A vanishing point can determine the unit direction vector of the corresponding parallel lines in the camera frame, and as input, the
Kai Guo +5 more
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A New Method for Absolute Pose Estimation with Unknown Focal Length and Radial Distortion [PDF]
Sensors, 2022 Estimating the absolute pose of a camera is one of the key steps for computer vision. In some cases, especially when using a wide-angle or zoom lens, the focal length and radial distortion also need to be considered.
Kai Guo, Hu Ye, Honglin Chen, Xin Gao
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Research on Focal Length Measurement Scheme of Self-Collimating Optical Instrument Based on Double Grating [PDF]
Sensors, 2020 In this paper, we propose a scheme for measuring the focal length of a collimating optical instrument. First, a mathematical model for measuring the focal length of a collimator with double gratings is derived based on the moiré fringe formula and the ...
Wenchang Yang +7 more
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6DoF Object Pose and Focal Length Estimation from Single RGB Images in Uncontrolled Environments [PDF]
SensorsAccurate 6DoF (degrees of freedom) pose and focal length estimation are important in extended reality (XR) applications, enabling precise object alignment and projection scaling, thereby enhancing user experiences.
Mayura Manawadu, Soon-Yong Park
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Millimeter-scale focal length tuning with MEMS-integrated meta-optics employing high-throughput fabrication [PDF]
Scientific Reports, 2022 Miniature varifocal lenses are crucial for many applications requiring compact optical systems. Here, utilizing electro-mechanically actuated 0.5-mm aperture infrared Alvarez meta-optics, we demonstrate 3.1 mm (200 diopters) focal length tuning with an ...
Zheyi Han +3 more
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Stretchable metalens with tunable focal length and achromatic characteristics
Results in Physics, 2021 We propose a stretchable metalens on polydimethylsiloxane (PDMS) substrate. By stretching the stretchable metalens device along x- and y-axis directions, it exhibits highly tunable focal length and achromatic characteristics.
Peng Lin +3 more
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Focal Length Affects Depicted Shape and Perception of Facial Images. [PDF]
PLoS ONE, 2016 Static photographs are currently the most often employed stimuli in research on social perception. The method of photograph acquisition might affect the depicted subject's facial appearance and thus also the impression of such stimuli.
Vít Třebický +3 more
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High-Performance PVC Gel for Adaptive Micro-Lenses with Variable Focal Length [PDF]
Scientific Reports, 2017 This paper presents a bio-inspired adaptive micro-lens with electrically tunable focus made of non-ionic high-molecular-weight polyvinyl chloride (PVC) gel. The optical device mimics the design of the crystalline lens and ciliary muscle of the human eye.
Jin Woo Bae +7 more
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The effect of various focal length photographs on eyewitness identification accuracy [PDF]
Proceedings of the Estonian Academy of Sciences, 2021 A key factor that has rarely been investigated regarding the technical details of photographs in eyewitness identification research is focal length. Focal length can be defined as the distance between the camera lens and the camera sensor, providing ...
Kristjan Kask +2 more
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Surface Topographical Control of a Liquid Crystal Microlens Array Embedded in a Polymer Network
Applied Sciences, 2022 A novel approach for fabricating a microlens array with a tunable surface topographical structure and focal length is proposed in the present study. The microlens array was manufactured through the photoinduced molecular reorientation of nematic liquid ...
Jose Carlos Mejia +6 more
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