Measurements of micro-focus spot size (0.005-0.1mm) in x-ray tubes and lenses

2005 ◽  
Author(s):  
Vladimir Y. Shovkun
Keyword(s):  
Spot Size ◽  
X Ray ◽  
Focus Spot ◽  
Focus Spot Size

scholarly journals Photonic Jet-Shaped Optical Fiber Tips versus Lensed Fibers

Photonics ◽  
2021 ◽  
Vol 8 (9) ◽  
pp. 373
Author(s):  
Djamila Bouaziz ◽  
Grégoire Chabrol ◽  
Assia Guessoum ◽  
Nacer-Eddine Demagh ◽  
Sylvain Lecler
Keyword(s):  
Optical Fiber ◽  
Optical Fibers ◽  
Single Mode ◽  
Spot Size ◽  
Base Diameter ◽  
Core Diameter ◽  
Focus Spot ◽  
Photonic Jet ◽  
Focus Spot Size ◽  
Focusing Properties

Shaped optical fiber tips have recently attracted a lot of interest for photonic jet light focusing due to their easy manipulation to scan a sample. However, lensed optical fibers are not new. This study analyzes how fiber tip parameters can be used to control focusing properties. Our study shows that the configurations to generate a photonic jet (PJ) can clearly be distinguished from more classical-lensed fibers focusing. PJ is a highly concentrated, propagative light beam, with a full width at half maximum (FWHM) that can be lower than the diffraction limit. According to the simulations, the PJs are obtained when light is coupled in the guide fundamental mode and when the base diameter of the microlens is close to the core diameter. For single mode fibers or fibers with a low number of modes, long tips with a relatively sharp shape achieve PJ with smaller widths. On the contrary, when the base diameter of the microlens is larger than the fiber core, the focus point tends to move away from the external surface of the fiber and has a larger width. In other words, the optical system (fiber/microlens) behaves in this case like a classical-lensed fiber with a larger focus spot size. The results of this study can be used as guidelines for the tailored fabrication of shaped optical fiber tips according to the targeted application.

Division of aperture to reduce the focus spot size

2000 ◽  
Author(s):  
Liangyu Li ◽  
Changchun Li ◽  
Huajun Yang ◽  
Yinzhu Li ◽  
Yaping Dai ◽  
...  
Keyword(s):  
Spot Size ◽  
Focus Spot ◽  
Focus Spot Size

Speckle pattern sequential extraction metric for estimating the focus spot size on a remote diffuse target

2017 ◽  
Vol 56 (32) ◽  
pp. 8941 ◽  
Author(s):  
Zhan Yu ◽  
Yuanyang Li ◽  
Lisheng Liu ◽  
Jin Guo ◽  
Tingfeng Wang ◽  
...  
Keyword(s):  
Sequential Extraction ◽  
Speckle Pattern ◽  
Spot Size ◽  
Focus Spot ◽  
Focus Spot Size

The determination of the focal spot size of an X-ray tube from the radiation beam profile

2015 ◽  
Vol 82 ◽  
pp. 138-145 ◽  
Author(s):  
A.D. Oliveira ◽  
M.J. Fartaria ◽  
J. Cardoso ◽  
L.M. Santos ◽  
C. Oliveira ◽  
...  
Keyword(s):  
Focal Spot ◽  
Spot Size ◽  
Beam Profile ◽  
Focal Spot Size ◽  
Radiation Beam ◽  
X Ray

scholarly journals Research on fiber coupling technology of kilowatt laser diode by single emitters

2018 ◽  
Vol 189 ◽  
pp. 11008 ◽  
Author(s):  
Wenbin Qin ◽  
Jing Li ◽  
Lei Yao ◽  
Youqiang Liu ◽  
Yuntao Qiu ◽  
...  
Keyword(s):  
Diode Laser ◽  
Coupling Efficiency ◽  
Processing System ◽  
Spot Size ◽  
Theoretical Research ◽  
Fiber Coupling ◽  
Output Laser Power ◽  
Fiber Taper ◽  
Output Laser ◽  
Focus Spot Size

This paper proposes a program that combine the laser of single-emitters by using fiber combiner, what’s more, we designed and developed a multiple single emitters diode laser module of full optical fiber. We used ZEMAX software to simulate and optimize the influence of fiber coupling efficiency by the location of cylindrical lens and fiber, finally, we developed 8W fiber coupling single emitter diode laser, the wavelength is 915nm, fiber diameter is 105/125μm, NA0.15. This article also carried on the theoretical research of N×1 fiber combiner, and based on Vytran GPX glass processing system, we fabricated the 19×1fiber combiner by TFB technique, combined 19 105/122μm, NA0.15 fibers to a 400/440μm, NA0.22 fiber, has realized 150W laser output, with fiber combining efficiency more than 96%. In the end, 8*400um fibers are synthesized through a fiber taper. The output laser power after fiber taper reached 1453W, with the focus spot size is 2.25mm*1.1mm and power density reached 6×104W/cm2.

scholarly journals Improve X-ray images using quality assurance tests

2021 ◽  
Vol 2114 (1) ◽  
pp. 012034
Author(s):  
M. W. Alhamd ◽  
Aqeel Maryoosh Jary ◽  
Sadeq Naeem Atiyah ◽  
Nazar Ali Abbood
Keyword(s):  
Quality Assurance ◽  
Light Field ◽  
Vertical Axis ◽  
Spot Size ◽  
International Standards ◽  
Focal Spot Size ◽  
X Ray ◽  
Medical Tests ◽  
Reference Doses ◽  
Congruence Test

Abstract In this research, entrance surface doses of patients which are resulted from a classical radiograph in most widespread tests (Chest, skull, abdomen, limbs, …) have been measured with selected instruments in (Specialized surgeries hospital) and one of the private clinic in Baghdad, the instruments are of various origins and different make date. A group of patients (10 patients) for each test and according the average of the resulted doses. Comparison of the patient’s doses, in this research, has been close with the reliable International standards and it has been found that radiological doses are bigger than reference doses ranging (132–1.79) in most of the appliance and the range doses to one whenever the instrument is new and the radiographer has good experience, this increase relates to several functions discussed in the research in detail For the importance of the quality assurance of x-ray instruments, three tests have been performed by three of the instruments only, and these tests are : Beam Alignment test : The Beam Alignment was measured and the x-ray radiograph was found symmetrical round the two axes of the instruments (A, B) but it is about 3 ° away from the vertical axis of the instrument (C). Optical and Radiation Field Congruence Test: The light field coincides with the radiative field in a and b and their mismatch in c. Focal Spot Size Test: The radiation focus area was measured by the star tool and what appeared is that the focus of the x-ray instrument (C) is smaller than the international standards on the contrary of the focus area of the x-ray instrument (E) which is identical with the international standards. From these results reached is that the instruments (A, B) have passed quality assurance tests and they are suitable for work in the present, but the instrument (C) has not passed most of the quality assurance tests, so this instrument should not be used for medical tests This in research is considered the first one for these instruments to evaluate their doses or measure a quality assurance.

scholarly journals 221. Effect of grid bias voltage on the focal spot size of microfocus X-ray tube

1993 ◽  
Vol 49 (8) ◽  
pp. 1246
Author(s):  
Seiichi Mimura ◽  
Noriaki Akagi ◽  
Fumie Kimura ◽  
Shigefumi Kadohisa ◽  
Yasutaka Mikami ◽  
...  
Keyword(s):  
Bias Voltage ◽  
Focal Spot ◽  
Spot Size ◽  
Focal Spot Size ◽  
X Ray
Sign in / Sign up

Export Citation Format

Share Document