Simultaneous fluorescence and high-resolution bright-field imaging with aberration correction over a wide field-of-view with Fourier ptychographic microscopy (FPM) (Conference Presentation)

Abstract The presence of a scattering medium in the imaging path between an object and an observer is known to severely limit the visual acuity of the imaging system. We present an approach to circumvent the deleterious effects of scattering, by exploiting spectral correlations in scattered wavefronts. Our Synthetic Wavelength Holography (SWH) method is able to recover a holographic representation of hidden targets with high resolution over a wide field of view. The complete object field is recorded in a snapshot-fashion, by monitoring the scattered light return in a small probe area. This unique combination of attributes opens up a plethora of new Non-Line-of-Sight imaging applications ranging from medical imaging and forensics, to early-warning navigation systems and reconnaissance. Adapting the findings of this work to other wave phenomena will help unlock a wider gamut of applications beyond those envisioned in this paper.

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On-Orbit Calibration Approach Based on Partial Calibration-Field Coverage for the GF-1/WFV Camera

Photogrammetric Engineering & Remote Sensing ◽

10.14358/pers.85.11.815 ◽

2019 ◽

Vol 85 (11) ◽

pp. 815-827 ◽

Cited By ~ 1

Author(s):

Mi Wang ◽

Beibei Guo ◽

Ying Zhu ◽

Yufeng Cheng ◽

Chenhui Nie

Keyword(s):

High Resolution ◽

High Accuracy ◽

Field Of View ◽

Estimation Methods ◽

Large Field ◽

Wide Field ◽

Optical Remote Sensing ◽

Calibration Data ◽

Stereoscopic Images ◽

Wide Field Of View

The Gaofen-1 (GF1) optical remote sensing satellite is the first in China's series of high-resolution civilian satellites and is equipped with four wide-field-of-view cameras. The cameras work together to obtain an image 800 km wide, with a resolution of 16 m, allowing GF1 to complete a global scan in four days. To achieve high-accuracy calibration of the wide-field-of-view cameras on GF1, the calibration field should have high resolution and broad coverage based on the traditional calibration method. In this study, a GF self-calibration scheme was developed. It uses partial reference calibration data covering the selected primary charge-coupled device to achieve high-accuracy calibration of the whole image. Based on the absolute constraint of the ground control points and the relative constraint of the tie points of stereoscopic images, we present two geometric calibration models based on paired stereoscopic images and three stereoscopic images for wide-field-of-view cameras on GF1, along with corresponding stepwise internal-parameter estimation methods. Our experimental results indicate that the internal relative accuracy can be guaranteed after calibration. This article provides a new approach that enables large-field-of-view optical satellites to achieve high-accuracy calibration based on partial calibration-field coverage.

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Optical System Design with High Resolution and Large Field of View for the Remote Sensor

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.364-366.550 ◽

2007 ◽

Vol 364-366 ◽

pp. 550-554

Author(s):

Jun Chang ◽

Zhi Cheng Weng ◽

Yong Tian Wang ◽

De Wen Cheng ◽

Hui Lin Jiang

Keyword(s):

High Resolution ◽

Optical System ◽

Design Method ◽

Field Of View ◽

Large Field ◽

Wide Field ◽

Remote Sensor ◽

Wide Field Of View ◽

Technological Developments ◽

Technological Opportunities

In this paper, we are presenting a design method and its results for a space optical system with high resolution and wide field of view. This optical system can be used both in infrared and visible configurations. The designing of this system is based on an on-axis three-mirror anastigmatic (TMA) system. Here the on-axis concept allows wide field of view (FOV) enabling a diversity of designs available for the Multi-Object Spectrometer instruments optimized for low scattered and low emissive light. The available FOVs are upto 1º in both spectrum ranges, whereas the available aperture range is F/15 - F/10. The final optical system is a three-mirror telescope with two on-axis and one off-axis segment and its resolution is 0.3m or even lower. The distinguished feature of this design is that it maintains diffraction-limited image at wide wavelengths. The technological developments in the field of computer generated shaping of large-sized optical surface details with diffraction-limited imagery have opened new avenues towards the designing techniques. Such techniques permit us to expand these technological opportunities to fabricate the aspherical off-axis mirrors for a complex configuration.

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Having your cake and eating it too: Wide field of view and high resolution VR

Journal of Vision ◽

10.1167/2.10.134 ◽

2002 ◽

Vol 2 (10) ◽

pp. 134-134

Author(s):

R. W. Massof ◽

L. Brown ◽

M. D. Shapiro ◽

G. D. Barnett ◽

F. H. Baker

Keyword(s):

High Resolution ◽

Field Of View ◽

Wide Field ◽

Wide Field Of View

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Visually Guided Microassembly with Active Zooming

Journal of Robotics and Mechatronics ◽

10.20965/jrm.2006.p0787 ◽

2006 ◽

Vol 18 (6) ◽

pp. 787-794

Author(s):

Xiaodong Tao ◽

◽

Hyungsuck Cho ◽

Youngjun Cho ◽

Keyword(s):

High Resolution ◽

Field Of View ◽

Depth Of Field ◽

Wide Field ◽

Small Field ◽

Depth Of Focus ◽

Large Depth ◽

Small Depth ◽

Wide Field Of View ◽

Small Field Of View

Vision techniques used in automatic microassembly are limited by inherent problems such as small depth of focus and small field of view. Microassembly must, however, initially detect microparts in a wide field of view and large depth of field while maintaining high resolution. We propose microassembly using active zooming that can overcome these limitations. For a small field of view, active zooming prevents the target from getting out of the field of view during microassembly. For a small depth of focus, our proposal is based on focus measure to maintain clear target image in the field of view during microassembly. Two-step assembly thus ensures zoom microscopy maintaining a wide field of view and large depth of field initially and high resolution at the end. Peg-in-hole assembly experiments confirmed the feasibility of our proposal.

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Observation of extremely thin insulating layers formed on a trench with an ultra-high-resolution scanning electron microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100086829 ◽

1991 ◽

Vol 49 ◽

pp. 504-505

Author(s):

K. Ogura ◽

J. Teshima

Keyword(s):

High Resolution ◽

Cross Section ◽

Chemical Etching ◽

Silicon Oxide ◽

Field Of View ◽

Specimen Preparation ◽

Wide Field ◽

Layer Formation ◽

Wide Field Of View ◽

Thick Layers

Observation of extremely thin insulating layers of silicon oxide and silicon nitride formed on a trench with a conventional EE SEM cannot be satisfactorily carried out by the conventional method to mechanically polish and chemically etch the wafer cross section and then investigate the state of layer formation from the uncvenness appearing on the cross section. One reason is that the resolution of the conventional FE SEM is not enough for the observation of several nm thick layers even if they arc etched. Another reason is that true layer thickness may be obscured by chemical etching. Those are why TEMs have been used for the observation of extremely thin insulating layers on trenches with atomic resolution. However, TEM application includes complicated specimen preparation, and does not allow observation of wide field of view. Therefore, the ultra-high resolution SEM (UHR SEM) has recently been used for similar purposes, using a simply cleaved plane of a wafer.

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Fabrication and Characterization of Curved Compound Eyes Based on Multifocal Microlenses

Micromachines ◽

10.3390/mi11090854 ◽

2020 ◽

Vol 11 (9) ◽

pp. 854 ◽

Cited By ~ 1

Author(s):

Gaoge Lian ◽

Yongshun Liu ◽

KeKai Tao ◽

Huaming Xing ◽

Ruxia Huang ◽

...

Keyword(s):

Compound Eye ◽

Accurate Method ◽

Field Of View ◽

Curved Surface ◽

Compound Eyes ◽

Wide Field ◽

Wide Field Of View ◽

Field Imaging ◽

Wide Field Imaging

Curved compound eyes have generated great interest owing to the wide field of view but the application of devices is hindered for the lack of proper detectors. One-lens curved compound eyes with multi-focal microlenses provide a solution for wide field imaging integrated in a commercial photo-detector. However, it is still a challenge for manufacturing this kind of compound eye. In this paper, a rapid and accurate method is proposed by a combination of photolithography, hot embossing, soft photolithography, and gas-assisted deformation techniques. Microlens arrays with different focal lengths were firstly obtained on a polymer, and then the planar structure was converted to the curved surface. A total of 581 compound eyes with diameters ranging from 152.8 µm to 240.9 µm were successfully obtained on one curved surface within a few hours, and the field of view of the compound eyes exceeded 108°. To verify the characteristics of the fabricated compound eyes, morphology deviation was measured by a probe profile and a scanning electron microscope. The optical performance and imaging capability were also tested and analyzed. As a result, the ommatidia made up of microlenses showed not only high accuracy in morphology, but also imaging uniformity on a focal plane. This flexible massive fabrication of compound eyes indicates great potential for miniaturized imaging systems.

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