Wide field of view, ultracompact static Fourier-transform spectrometer

1997 ◽  
Vol 68 (1) ◽  
pp. 30-33 ◽  
Author(s):  
D. Steers ◽  
B. A. Patterson ◽  
W. Sibbett ◽  
M. J. Padgett
Keyword(s):  
Fourier Transform ◽  
Field Of View ◽  
Wide Field ◽  
Fourier Transform Spectrometer ◽  
Wide Field Of View

scholarly journals TSUNAMI EARLY DETECTION:ENHANCED RESOLUTION OF HF OCEANOGRAPHIC RADAR

2011 ◽  
Vol 1 (32) ◽  
pp. 4 ◽  
Author(s):  
Yasuhiro Murata ◽  
Toshiro Nagakura ◽  
Takahiro Kokai
Keyword(s):  
Fourier Transform ◽  
Surface Current ◽  
Sea Surface ◽  
Field Of View ◽  
Wide Field ◽  
Short Time Fourier Transform ◽  
Zero Padding ◽  
Wide Field Of View ◽  
Short Time ◽  
Doppler Analysis

HF Oceanographic radar is an equipment, for instantaneously sensing velocity distribution of sea surface current. It has a wide field of view, which extends approximately ±45° in direction and beyond 50km in distance. There are high expectations that the radar observation of Tsunami will become a new road path for preventing disasters. In this paper, we describe a method to enhance the resolutions of radar in both time and current. At first, resolutions required for tsunami observation are estimated by simulating a Tokachi-oki earthquake tsunami (2003). Here it is pointed out that traditional data processing indicates inadequate resolutions for tsunami early detection. Secondly, two techniques are proposed to achieve the necessary resolutions. Short-time Fourier transform (STFT), in place of normal FFT, enhances the time resolution of Doppler analysis. Further, zero-padding technique improves the current resolution, by interpolation of data within the frequency domain. Finally, by means of simulation, it is verified that these proposed techniques give improved resolutions in both time and current.

Study of Fourier Transform Imaging Spectrometer with Wide Field of View

2016 ◽  
Vol 36 (1) ◽  
pp. 0130001
Author(s):  
张智南 Zhang Zhinan ◽  
李立波 Li Libo ◽  
胡炳樑 Hu Bingliang ◽  
冯玉涛 Feng Yutao
Keyword(s):  
Fourier Transform ◽  
Field Of View ◽  
Wide Field ◽  
Imaging Spectrometer ◽  
Wide Field Of View

STM studies of crystal growth

1991 ◽  
Vol 49 ◽  
pp. 374-375
Author(s):  
M. G. Lagally
Keyword(s):  
Crystal Growth ◽  
Molecular Beam ◽  
Chemical Vapor ◽  
Sputter Deposition ◽  
Field Of View ◽  
Scanning Tunneling ◽  
Wide Field ◽  
Tunneling Microscopy ◽  
Wide Field Of View ◽  
The One

It has been recognized since the earliest days of crystal growth that kinetic processes of all Kinds control the nature of the growth. As the technology of crystal growth has become ever more refined, with the advent of such atomistic processes as molecular beam epitaxy, chemical vapor deposition, sputter deposition, and plasma enhanced techniques for the creation of “crystals” as little as one or a few atomic layers thick, multilayer structures, and novel materials combinations, the need to understand the mechanisms controlling the growth process is becoming more critical. Unfortunately, available techniques have not lent themselves well to obtaining a truly microscopic picture of such processes. Because of its atomic resolution on the one hand, and the achievable wide field of view on the other (of the order of micrometers) scanning tunneling microscopy (STM) gives us this opportunity. In this talk, we briefly review the types of growth kinetics measurements that can be made using STM. The use of STM for studies of kinetics is one of the more recent applications of what is itself still a very young field.

Design and verification of high-precision multi-star simulator with a wide field of view

2020 ◽  
Vol 13 (6) ◽  
pp. 1-9
Author(s):  
XU Hong-gang ◽  
◽  
HAN Bing ◽  
LI Man-li ◽  
MA Hong-tao ◽  
...  
Keyword(s):  
High Precision ◽  
Field Of View ◽  
Wide Field ◽  
Wide Field Of View

Fabrication of bioinspired omnidirectional and gapless microlens array for wide field-of-view detections

2012 ◽  
Vol 100 (13) ◽  
pp. 133701 ◽  
Author(s):  
Hewei Liu ◽  
Feng Chen ◽  
Qing Yang ◽  
Pubo Qu ◽  
Shengguan He ◽  
...  
Keyword(s):  
Microlens Array ◽  
Field Of View ◽  
Wide Field ◽  
Wide Field Of View

scholarly journals Wide field-of-view lens-free fluorescent imaging on a chip

Lab on a Chip ◽  
2010 ◽  
Vol 10 (7) ◽  
pp. 824 ◽  
Author(s):  
Ahmet F. Coskun ◽  
Ting-Wei Su ◽  
Aydogan Ozcan
Keyword(s):  
Fluorescent Imaging ◽  
Field Of View ◽  
Wide Field ◽  
Wide Field Of View

scholarly journals Wide field-of-view crossed Dragone optical system using anamorphic aspherical surfaces

2018 ◽  
Vol 57 (15) ◽  
pp. 4171 ◽  
Author(s):  
Shingo Kashima ◽  
Masashi Hazumi ◽  
Hiroaki Imada ◽  
Nobuhiko Katayama ◽  
Tomotake Matsumura ◽  
...  
Keyword(s):  
Optical System ◽  
Field Of View ◽  
Wide Field ◽  
Wide Field Of View

Fisheye lens camera based surveillance system for wide field of view monitoring

Optik ◽  
2016 ◽  
Vol 127 (14) ◽  
pp. 5636-5646 ◽  
Author(s):  
Hyungtae Kim ◽  
Jaehoon Jung ◽  
Joonki Paik
Keyword(s):  
Surveillance System ◽  
Field Of View ◽  
Wide Field ◽  
Fisheye Lens ◽  
Wide Field Of View

scholarly journals Global and regional evaluation of over-land spectral aerosol optical depth retrievals from SeaWiFS

2012 ◽  
Vol 5 (2) ◽  
pp. 2169-2220 ◽  
Author(s):  
A. M. Sayer ◽  
N. C. Hsu ◽  
C. Bettenhausen ◽  
M.-J. Jeong ◽  
B. N. Holben ◽  
...  
Keyword(s):  
North America ◽  
Aerosol Optical Depth ◽  
Optical Depth ◽  
Field Of View ◽  
Wide Field ◽  
Imaging Spectrometer ◽  
Wide Field Of View ◽  
Moderate Resolution ◽  
Resolution Imaging ◽  
Multiangle Imaging

Abstract. This study evaluates a new spectral aerosol optical depth (AOD) dataset derived from Sea-viewing Wide Field-of-view Sensor (SeaWiFS) measurements over land. First, the data are validated against Aerosol Robotic Network (AERONET) direct-sun AOD measurements, and found to compare well on a global basis. If only data with the highest quality flag are used, the correlation is 0.86 and 72% of matchups fall within an expected absolute uncertainty of 0.05 + 20% (for the wavelength of 550 nm). The quality is similar at other wavelengths and stable over the 13-yr (1997–2010) mission length. Performance tends to be better over vegetated, low-lying terrain with typical AOD of 0.3 or less, such as found over much of North America and Eurasia. Performance tends to be poorer for low-AOD conditions near backscattering geometries, where SeaWiFS overestimates AOD, or optically-thick cases of absorbing aerosol, where SeaWiFS tends to underestimate AOD. Second, the SeaWiFS data are compared with midvisible AOD derived from the Moderate Resolution Imaging Spectrometer (MODIS) and Multiangle Imaging Spectroradiometer (MISR). All instruments show similar spatial and seasonal distributions of AOD, although there are regional and seasonal offsets between them. At locations where AERONET data are available, these offsets are largely consistent with the known validation characteristics of each dataset. With the results of this study in mind, the SeaWiFS over-land AOD record is suitable for quantitative scientific use.

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