A universal pyrometer for molecular-beam epitaxy setups

A universal fiber-optic pyrometer for the molecular-beam-epitaxy growth module developed in collaboration with JSC Semiconductor Technologies and Equipment is described. This instrument is designed for controlling the technological process of growing semiconductor heterostructures on substrates of various types (GaAs, InP, Si, and sapphire). The pyrometer allows measurements of the temperature of semiconductor substrates to be performed in the range 450–1200°C with an accuracy no worse than ±0.5% under the conditions when such characteristics as the emissivity of the material, the transparency of the optical medium, and the dimensions of the studied surface are unknown. These feasibilities can be realized owing to the use of a procedure of periodic calibration of the pyrometer against an actual object directly during the technological cycle with the use of additional information on the object temperature.     

Fast fiber-optic multi-wavelength pyrometer

A fast fiber-optic multi-wavelength pyrometer was developed for the ultraviolet-visible-near infrared spectra from 200 nm to 1700 nm using a CCD detector and an InGaAs detector. The pyrometer system conveniently and quickly provides the sufficient choices of multiple measurement wavelengths using optical diffraction, which avoids the use of narrow-band filters. Flexible optical fibers are used to transmit the radiation so the pyrometer can be used for temperature measurements in harsh environments. The setup and calibrations (wavelength calibration, nonlinearity calibration, and radiation response calibration) of this pyrometer system were described. Development of the multi-wavelength pyrometer involved optimization of the bandwidth and temperature discrimination of the multiple spectra data. The analysis results showed that the wavelength intervals, Δλ(CCD) = 30 nm and Δλ(InGaAs) = 50 nm, are the suitable choices as a tradeoff between the simple emissivity model assumption and the multiple signal discrimination. The temperature discrimination was also quantificationally evaluated for various wavelengths and temperatures. The measurement performance of the fiber-optic multi-wavelength pyrometer was partially verified through measurements with a high-temperature blackbody and actual hot metals. This multi-wavelength pyrometer can be used for remote high-temperature measurements.     

辐射光纤高温计及其系统的研究

为解决特殊情况下的高温在线测量，研制了一种辐射光纤高温计。介绍了仪表的工作原理、光滤波及测试结果的处理。     

Multiwavelength optical pyrometer for shock compression experiments

A system for measurement of the spectral radiance of materials shocked to high pressures ( approximately 100 GPa) by impact using a light gas gun is described. Thermal radiation from the sample is sampled at six wavelength bands in the visible spectrum, and each signal is separately detected by solid-state photodiodes, and recorded with a time resolution of approximately 10 ns. Interpretation of the records in terms of temperature of transparent sample materials is discussed. Results of a series of exploratory experiments with metals are also given. Shock temperatures in the range 4000-8000 K have been reliably measured. Spectral radiance and temperatures have been determined with uncertainties of 2%.     

Two-color optical charge-coupled-device-based pyrometer using a two-peak filter

A two-color optical charge-coupled-device (CCD)-based pyrometer was developed using a multipeak interference filter with a color CCD sensor to measure multicolor signals with specified wavelengths. The effective and simple method adjusts the fixed spectrum response characteristics of a color CCD to allow improved temperature measurements. This pyrometer system not only has the advantage of traditional two-color (two-wavelength) pyrometry, but also overcomes the restrictions of color CCDs that can only be applied in waveband measurements. The measurement performance of the system using a two-peak filter (λ(1)=643?nm,?λ(2)=564?nm) was evaluated by blackbody experiments. The results show that the low temperature detection limit is increased about 200 K with an increase in the sensitivity of the measured signals compared with the original system without two-peak filter [Fu, et al., Opt. Laser Technol. 42, 586 (2010)]. And the effective temperature range is also increased when T > 1233 K. The measured ratio C(R)/C(G) is monotonically relative to the temperature, which simplifies the measurements. The temperature sensitivity of 2.49 is larger and more uniform than the temperature sensitivity of 1.36 in the previous original system. Thus, the measurement performance of the new system is greatly improved. Finally, as an application, the surface temperature distribution of stainless steel sample in hot environments was determined by this new CCD-based pyrometer. The results agree well with the spectrometer-based results and further verify the applicability of the new system.     

Scanning optical pyrometer for measuring temperatures in hollow cathodes

Life-limiting processes in hollow cathodes are determined largely by the temperature of the electron emitter. To support cathode life assessment, a noncontact temperature measurement technique which employs a stepper motor-driven fiber optic probe was developed. The probe is driven inside the hollow cathode and collects light radiated by the hot interior surface of the emitter. Ratio pyrometry is used to determine the axial temperature profile. Thermocouples on the orifice plate provide measurements of the external temperature during cathode operation and are used to calibrate the pyrometer system in situ with a small oven enclosing the externally heated cathode. The diagnostic method and initial measurements of the temperature distribution in a hollow cathode are discussed.     

光电高温计在双辉等离子渗金属测温中的应用研究

为准确测量双辉等离子渗金属中的工件温度，借助自行研制的一套热电偶测温实验装置，采用比对实验的手段，得出了在碳钢表面常规双辉等离子渗金属过程中，准确选定光电高温计的材料发射率修正系数的方法。     

Methodology for spectral emissivity measurement by means of single color pyrometer

The application of non-intrusive optical devices, such as infrared pyrometers able to measure the temperature of surfaces, makes possible the evaluation of emissivity curve of the tested materials at different temperature values. In this paper the authors propose a methodology for the spectral emissivity measurement by means of a single color pyrometer providing a semi-empirical formula, obtained experimentally at CIRA’s laboratory. The semi-empirical formula allows to know the actual emissivity value of the sample’s surface for whatever emissivity value set up on the pyrometer. The agreement between the experimental emissivity and the emissivity predicted by semi-empirical formula was verified.     

一种新颖的增压装置

我厂是生产气动元件历史比较长的厂家,主要生产各类型,各种规格的气缸,气动换向阀,流量控制阀,包装机械以及各种气动系统气控柜等。这些产品按产品质量标准要求,应不定期做抽样耐压试验。以前由于厂里条件限制,产品在做耐压试验时只能在实验室里进行,由于车间与实验室相距较远,很不方便,为解决这一矛盾,我们设计了一套增压装置来产生高压气源,以完成气缸、阀等待测件出厂前的质检工作。１　增压装置的结构及增压原理本增压装置系统原理图见图１,其中双作用增压缸,高压单向阀,高压节流阀是自行设计的。１．双作用增压气缸　２…     

一种新型振动给料机

目前的输送设备多为单质体和双质体输送机。单质体输送机结构简单，但对基础作用力大；双质体输送机一般为电磁振动输送机，振幅较小，处理量小，而双质体悬挂式输送机结构又较松散。为了克服现有技术的不足，本文提供一种单轴惯性振动给料机，特别适于煤炭、水泥、陶瓷、冶金等行业输送粒度为0～300mm的混合散料。     

一种新型光学编码器

光学编码器是长度和角度测量最常用的传感器,两种传统光学编码器:绝对式和增量式光学编码器的光学图案、位置编码原理和信号处理电路各具特色,随着科学技术的发展,一种新型光学编码器方案:准绝对式编码器,继承了二者的优点,根据其串行位置编码原理,借助计算机辅助设计,获得了全周100个位置的编码方案,设计了相应的准绝对式编码器;通过与两种传统编码器特点的比较,突出了准绝对式光学编码器的显著特点,指明了其未来良好的应用和发展前景.     

一种新型扭矩扳手

介绍了一种可预先设定扭矩值的扭矩扳手的结构组成、工作原理;还对扳手的各主要元器件的结构设计,计算及加工制造进行了描述。     

一种新型旋转式刀库

针对小型机床配对刀库难的问题,从理论设计的角度,提出了一种新型的刀库设计方案--旋转式刀库.为小型数控机床配对刀库提供更多的选择方式.     

A new deal?

John Towers explains the background to `Rover Tomorrow ? the New Deal?, a historic agreement aimed at securing long term growth and prosperity through a new partnership with the company's employees and suppliers.     

一种新型电液伺服阀

简要介绍一种由微型无刷直流电流电机直接驱动的单级电液伺服阀,它的阀芯驱动部分带有电反馈装置,因此具有高可靠性及良好的动态特性及很强的抗污染能力。是一种可用于军用仿真转台和工业领域的新型电液伺服元件。