Emissivity-compensated radiation thermometry method using a concave mirror

2021 ◽  
Vol 92 (5) ◽  
pp. 054903
Author(s):  
D. Terada ◽  
T. Iuchi
Keyword(s):  
Radiation Thermometry ◽  
Concave Mirror

Detection method of combustion oscillation characteristics under strong noise background

2020 ◽  
Vol 21 (6) ◽  
pp. 612
Author(s):  
Yunkun Wei ◽  
Tianhong Zhang ◽  
Zhonglin Lin ◽  
Qi Xie ◽  
Yan Zhang
Keyword(s):  
Radiation Thermometry ◽  
Hydroxyl Group ◽  
Interference Signal ◽  
Engine Vibration ◽  
Combustion Technology ◽  
Lean Fuel ◽  
Combustion Oscillation ◽  
Aero Engines ◽  
Temperature Measurement System ◽  
Multispectral Radiation Thermometry

After the lean fuel premixed combustion technology is applied to aero engines, severe combustion oscillations will be cased and led to hidden safety hazards such as engine vibration, further energy waste and other problems. Therefore, it is increasingly important to actively control combustion oscillations. In this paper, a multispectral radiation thermometry (MRT) is used to analyze the hydroxyl group, which is a measurable research object in the combustion chamber of an aero engine, and to fit the functional relationship between the radiation intensity ratio and the temperature in different bands. The theoretical value of the error is <2%. At the same time, in order to solve the problem of weak detection signal and excessive interference signal, an improved frequency domain filtering method based on fast Fourier transform is designed. Besides, the FPGA platform is used to ensure the real-time performance of the temperature measurement system, and simulations and experiments are performed. An oscillating signal with an oscillation frequency of 315 Hz is obtained on the established test platform, and the error is only 1.42%.

Ambient temperature-independent dual-band mid-infrared radiation thermometry

2016 ◽  
Vol 55 (9) ◽  
pp. 2169 ◽  
Author(s):  
You Lü ◽  
Xin He ◽  
Zhong-Hui Wei ◽  
Zhi-Yuan Sun ◽  
Song-Tao Chang
Keyword(s):  
Ambient Temperature ◽  
Infrared Radiation ◽  
Radiation Thermometry ◽  
Dual Band ◽  
Mid Infrared

QUINACRINE FLUORESCENCE AND Q-BANDING PATTERNS OF HUMAN CHROMOSOMES.: I. Effects of Varying Factors

1975 ◽  
Vol 17 (1) ◽  
pp. 81-92 ◽  
Author(s):  
C. C. Lin ◽  
H. van de Sande ◽  
W. K. Smink ◽  
D. R. Newton
Keyword(s):  
Exposure Time ◽  
Uv Light ◽  
Human Chromosomes ◽  
Concave Mirror ◽  
Banding Patterns ◽  
Fluorescent Microscope ◽  
Sperm Dna ◽  
Quinacrine Fluorescence ◽  
Well Differentiated ◽  
Salmon Sperm Dna

Various factors involved in the production of "Q-bands" have been studied. It was found that a Zeiss standard WL fluorescent microscope required a shorter exposure time for photography as compared to a Zeiss photomicroscope. The minimal exposure time was obtained when the standard WL microscope was equipped with a UV light source containing a DC powered mercury burner and a concave mirror. Further, the pH and type of water used in the staining, washing and mounting of the slide were also important factors in producing clear and well differentiated "Q-bands". It also appears that the factors involved in the production of "Q-bands" effect the enhancement or quenching of fluorescence by poly d(A-T).poly d(A-T) and salmon sperm DNA or poly dG∙poly dC respectively. This preliminary report also suggests that DNA or polynucleotides with a specific base sequence may play an important role in Q-banding patterns on chromosomes.

Analysis of Interferometer with Micro-Mirror on Beam Splitting Cube

2021 ◽  
pp. 129-143
Author(s):  
L.N. Timashova ◽  
N.N. Kulakova
Keyword(s):  
Interference Pattern ◽  
Fourier Transforms ◽  
Design Parameters ◽  
Spherical Mirror ◽  
Topographic Map ◽  
Wave Surface ◽  
Beam Splitting ◽  
Concave Mirror ◽  
Part Surface ◽  
Wave Aberration

The control of the shape of the optical part surface by the interference method has become an integral part of the process of their shaping. With a precisely focused interferometer interferometry allows obtaining an interference pattern similar to a topographic map of the error profile of the wave surface under investigation. The interferometer must form a map of the optical surface with high accuracy --- the permissible distortion of the interference fringe caused by an interferometer error should not exceed 0.1 of the distortion value caused by an error on the examined surface. The dependence of the interference pattern formation on the errors in the arrangement of the interferometer components, i.e., defocusing, was theoretically analyzed using Fourier transforms. The analysis was performed for an interferometer containing a laser illuminator, a concave spherical mirror with a central hole, coaxial to the illuminator, and a beamsplitting element in the form of a cube-prism with a semitransparent hypotenuse face. On the first flat face of the cube-prism, a microspherical concave mirror is made with the center located on the optical axis of the interferometer. A method for calculating the defocusing of a controlled spherical mirror and the corresponding wave aberration of the working wavefront is presented. An example of calculating the design parameters of the interferometer and the permissible defocusing of the controlled spherical mirror is given

Concave Mirror with Eagle, Chain, and Ball

1912 ◽  
Vol s11-VI (146) ◽  
pp. 297-297
Author(s):  
F. E. R. Pollard-Urquhart
Keyword(s):  
Concave Mirror
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