Dr. Jinyuan Liu Profile

Dr. Jinyuan Liu

at National Institute of Metrology

SPIE Involvement:

Author

Publications (3)

This will count as one of your downloads.

You will have access to both the presentation and article (if available).

DOWNLOAD NOW

This content is available for download via your institution's subscription. To access this item, please sign in to your personal account.

Email or Username Forgot your username?

Password Forgot your password?

Show

Keep me signed in

No SPIE account? Create an account

Proceedings Article | 30 April 2024 Paper

Research of non-linearity correction in infrared spectral radiance measurement

Shufang He, Ruoduan Sun, Yanfei Wang, Caihong Dai, Jinyuan Liu, Guojin Feng, Jinghui Wang

Proceedings Volume 13154, 131540G (2024) https://doi.org/10.1117/12.3018626

KEYWORDS: Infrared radiation, Black bodies, FT-IR spectroscopy, Spectral response

Read Abstract +

The nonlinear effect is one of the characteristics of photodetectors. In infrared measurement systems, photodetectors like MCT, InGaAs and InSb are widely used; while their non-linearity is still a problem. National Institute of Metrology, China has built an infrared spectral radiance measurement system. The system consists of a variable temperature blackbody as the standard radiation source; and uses a Fourier transform Infrared Spectrometer as the measuring instrument, including a MCT detector which is the main source of non-linearity uncertainty. In this study, an interpolation method and a polynomial fitting method are used to correct the non-linearity of the measurement system. To do so, at first, set the temperature of the standard variable blackbody to a serial of different temperatures, and use the measurement system to acquire the spectral response signal at each temperature; then, calculate the spectral radiance value of the standard radiation source based on the Planck’s law; after that, in the spectral dimension, analyze the relationship between and , and correct its non-linearity with a piecewise linear interpolation method and a multi-order polynomial fitting method; finally, verify the above two methods and analyze the relative deviation accordingly. The results show, the deviation is relatively large in wavelength range smaller than 8μm; while in 8μm~14μm wavelength range, the relative deviation is around 0.5%~0.001% and around 1.0%~0.001% by using the piecewise linear interpolation method and polynomial fitting method, respectively.

Proceedings Article | 18 December 2019 Paper

Analysis and suppression of stray radiation in infrared spectral radiation measurement

Shufang He, Yanfei Wang, Caihong Dai, Jinyuan Liu, Guojin Feng

Proceedings Volume 11337, 1133704 (2019) https://doi.org/10.1117/12.2540466

KEYWORDS: Infrared radiation, Optical simulations, FT-IR spectroscopy

Read Abstract +

The absolute measurements of spectral radiance, irradiance and intensity in infrared wave range are very important for infrared target recognition, material emissivity measurement and so on. Recently, many researchers focus on how to accurately measure absolute infrared spectral radiation, in which one key point is how to suppress stray radiation. In this paper, an absolute infrared spectral radiance measurement system was built up. The system contained a fixed-point blackbody source, a variable temperature blackbody source, a radiant source to be measured, Fourier Transform Infrared Radiometer (FTIR), optical system, non-contact infrared thermometer and so on. Emissivities of the standard source and the radiant source to be measured are 0.999 and 0.995, respectively. According to Planck’s law, their absolute spectral radiance should be similar at the same radiation temperature. In experiment, temperatures of the standard blackbody and radiant source to be measured were set to 500°C, and the FTIR was used to measure spectral radiance. The results show spectral radiance of the standard source is 14.9% smaller than the radiant source to be measured at 10μm wavelength. A thermal infrared imager and optical simulation software were used to analyze the possible reasons. To solve the problems, a shielding plate and a field aperture was installed respectively at the entrance of the optical system and before the FTIR to suppress stray radiation. Moreover, sizes and positions of the shielding plate, optical system, and field aperture were analyzed by optical simulation software and mathematical calculation. After optimization, the experimental results show the difference of spectral distributions between the standard source and the radiant source to be measured is only 1.42% at 10 μm wavelength, suggesting stray radiation is effectively suppressed in the system.

Proceedings Article | 18 November 2019 Paper

System construction and uncertainty evaluation of absolute measurement of infrared spectral radiance

Shufang He, Yanfei Wang, Caihong Dai, Jinyuan Liu, Guojin Feng

Proceedings Volume 11189, 111891A (2019) https://doi.org/10.1117/12.2537206

KEYWORDS: Infrared radiation, FT-IR spectroscopy, Radiometry, Optical metrology

Read Abstract +

The absolute measurement of infrared spectral radiance is very important for optical radiometry. In this paper, a system for absolute measurement of infrared spectral radiance is built up. The system consists of fixed-point blackbody sources, a variable temperature blackbody, a radiant source to be measured, Fourier Transform Infrared Radiometer (FTIR), relay optical system, non-contact infrared thermometer and so on. The emissivity of the variable temperature blackbody is 0.999; the temperature range is 50°C ~ 1050°C. The emissivity of the radiant source to be measured is larger than 0.995; the temperature range is 30°C ~ 550°C. The variable temperature blackbody source was calibrated and can be traced to the fixed-point blackbody source. In experiment, it was used as the standard radiant source. The spectral range of this system is 3 μm ~ 14 μm. A serial of experiments have been implemented to analyze the uncertainty of each component, including the repeatability, size-of-source effect, stability, uniformity and so on. To improve the system’s uncertainty, we have suppressed stray radiation and optimized optical system by installing a water-cooled aperture and a field stop at the entrance of the optical system and before the FTIR, respectively; optimizing the system based on optical simulation and replacing the reflective mirrors with one off-axis parabolic mirror. Next step, we will re-evaluate the uncertainty of the improved system.

My Library

You currently do not have any folders to save your paper to! Create a new folder below.

Folder Name

Folder Description

View contact details

UPDATE YOUR PROFILE

Is this your profile? Update it now.

Sign into your SPIE.org account

Don’t have a profile and want one?

Create an account on SPIE.org

Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks. You are receiving this notice because your organization may not have SPIE eBooks access.*

*Shibboleth/Open Athens users─please sign in to access your institution's subscriptions.

To obtain this item, you may purchase the complete book in print or electronic format on SPIE.org.

ORGANIZATIONAL
Sign in with credentials provided by your organization.

Organizational Username

Organizational Password

Show/Hide Password

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members:

Non-members: ADD TO CART

Keywords/Phrases

Search In:

Publication Years