本科生毕业论文(设计)

文献翻译原文

英文题目 An improved method of angle measurement with a position sensitive detector

中文题目 一种基于PSD器件的改进型角度测量方法

An improved method of angle measurement with

a position sensitive detector

Defeng Zheng^1,2, Xiangzhao Wang¹, and Feng Tang¹

¹Information Optics Laboratory, Shanghai Institute of Optics and Fine Mechanics,

Chinese Academy of Sciences, Shanghai 201800

²Graduate School of the Chinese Academy of Sciences, Beijing 100039

Received February 13, 2007

An improved method of angle measurement is proposed based on a parallel plate interferometer. A position detection system is incorporated into a parallel plate interferometer in order to realize large deflection angle measurement. A reflecting mirror is introduced for increasing the measurement resolution. In experiments, a deflection angle of a measured target was measured within}30with high accuracy. And as a phase modulating interferometer, it was used to measure a small angular displacement with a repeatability of 5.5 times;10^-8rad.

OCIS codes: 120.3180, 120.4640, 120.0120.

The angle measurement has widespread applications in the fields of alignment, assembly, and precision control. It is conventionally performed by using either autocollimators or interferometers. Besides, other techniques are often used. Generally, the anglemeasurement needs to be done with high stabilization and high accuracy in order to increase the automated production level and satisfy the demands of high efficiency in precision control.

A parallel plate interferometer for measuring angular displacement has been proposed by our research group[8].The plane-parallel plate has a simple structure itself, and it converts the angular displacement of a measured target into the phase difference of interference signal.Owing to the fact that a standard reference surface is not required in this optical configuration,the interferometer is stable and compact. But this interferometer can only measure the dynamic angle variation within a small measurement range, and it is not suitable to measure the deflection angle of a measured target within a relatively large range. In addition, it is not convenient for the field testing because the charge coupled device (CCD) is sensitive to the stray light. The angle measurement needs to be done in a dark room.

In this paper, an improved angle measurement method is proposed based on the above situation. An optical system using a position sensitive detector (PSD) and a lens is incorporated in order to enlarge the angle measurement range. And a reflecting mirror is introduced for increasing the measurement resolution. The improved interferometer not only can measure dynamic small angle variation with higher accuracy, but also can measure a relatively large deflection angle whose range is far thousand times larger than the variation range of small angle described in Ref. [8]. The analysis and experimental results prove that the improved interferometer can measure the angle with high accuracy.

The setup for angle measurement is shown in Fig.l.The light beam from the laser diode(LD) is collimated by a micro objective, and then is reflected several times in the system composed of a measured target and a reflecting mirror. The light beam is incident on the plane-parallel plate where the two reflected beams interfere with each other. The interference signal is detected by a photo diode. The transmitted beam from the plane-parallel plate is focused into a spot by a lens. The measurement setup consists of two measurement units. One is used for measuring relatively large angle based on position detection technique; the other is used for measuring dynamic small angle variation based on phase modulating interferometry.

In the process of assembly and alignment, the deflection angle can be measured as follows. The collimated beam A is incident on the measured target shown in Fig.2. Let i and m be the incident angle on the plane-parallel plate and the number of the reflections,

Fig 1 Experimental setup for angle measurement.

Fig 2 Amplification of the incident angle of the beam and

two beams reflected from the plane-parallel plate.

Fig 3 Measurement of the incident angle using a PSD.

respectively. If the measured target rotates A from the original place, the incident angle can be expressed as

In Eq.(1), the incident angles i and i} can be measured by the system shown in Fig. 3.The photo surface of the PSD just locates on the focal plane of the lens. According to geometrical optics, the incident angle is respectively given by

where f is the focal length of the lens, d and d} are the offsets of light spot deviating from the center of the PSDs photo surface. The offsets d and d} can be obtained according to the output voltage of the PSD. It follows from Eqs. (1) and (2) that the measured deflection angle is given by

where i=i-i.Figure 4 shows the relationship between i/2m and offset d,d in the case of m=3 and f = 30 mm. In Fig.4, 4d=d-d.The value of a depends on the value of light spots shifting on the PSD. Owing to the fact that the intensity of the light spot is very high, the method based on the PSD to measure the angle of incidence is insensitive to the stray light

Fig 4 Relation

剩余内容已隐藏，支付完成后下载完整资料

---

本科生毕业论文(设计)

文献翻译译文

英文题目 An improved method of angle measurement with a position sensitive detector

中文题目 一种基于PSD器件的改进型角度测量方法

学生姓名 黄丹丹

学 号 20131305042

学 院 电子与信息工程学院

专 业 电子信息工程

指导教师 张秀再

二Ｏ一 七 年 四 月 十八 日

一种基于PSD器件的改进型角度测量方法

郑德锋^1,2，王向朝¹，唐锋¹

¹光信息实验室，中国科学院上海光学精密机械研究所，上海201800

²中国科学院研究生院，北京100039

接收于2007.2.13

摘 要:提出一种基于平行平板干涉仪的改进型角度测量方法。为了实现较大的偏转角测量，该平行平板干涉仪引入了一位置探测系统。平面反射镜的引入提高了角度测量的分辨率。实验验证了可在近3度的范围内实现被测偏转角度的高精度测量。并且作为一位相调制型干涉仪，其小角位移测量实验的重复精度可达5.5times;10^-8rad。

光学分类与标引体系表代码:120.3180, 120.4640, 120.0120.

角度测量在校正、装配和精确控制领域有广泛应用。它习惯上用自准直仪^[1,2]或干涉仪^[3,4]来测量。并且其他的技术^[5-7]也经常用到角度测量。通常，为了提高生产自动化水平和发展高效率的精度控制的需求，角度测量需要做到高稳定和高精度。

我们研究小组己经提出了用平行板干涉仪测量角位移的方法^[8]。平行平板干涉仪的自身结构很简单，它把测量目标的角位移转化成干涉信号的不同相位。由于在这种光学装置不需要标准参考表面，干涉仪是稳定和紧凑的。但是，这种干涉仪的只能测量小范围的动态角度变化，并不是适用于测量具有较大范围偏转角度的测量的目标。此外，因为电荷祸合器件(CCD)对散射光敏感，它不能方便地进行现场测量。角度测量需要做在一个黑暗的房间里进行。

在这篇论文中，提出了一种基于上述情况的改进的角度测量方法。为了扩大角度测量的范围，使用了位置敏感探测器(PSD)和镜头组成的光学系统。为了增加测量分辨率使用了反射镜。改进的干涉不仅可以高精度测量动态小范围角度变化，也可以测量其范围是在Ref所描述的小角度超过几千倍^[8]的相对较大的偏角。分析和实验结果证明改进的干涉仪可以用于高精度的角度测量。

角度测量的装置如图1所示。从激光二极管(LD)发出的光束由一micro object校准，然后在测量的目标和反射镜组成的系统中多次反射。发出的光束是由两束反射光互相干涉的平面平行板上形成的。光电二极管检测到的干涉信号。从平面平行板的传送的光束经透镜聚焦成一个点。测量装置由两个测量单元组成。一个单元用来测量基于位置检测技术的相对较大的角度;另一个用于测量基于相位调制干涉的动态小角度变化。

在装配工艺和校准中，偏转角可以用如下方式测量，在图2中平行的光束A由测量目标产生。让由平面平行板和大量反射光产生的i和m分别成为入射角。如果测量的目标从原来的位置旋转e，入射角可以表达为

在等式(1)中入射角焦平面生成根据几何光学，i和irsquo;能用图3所示的系统测量。将PSD表面的像由镜头的入射角分别由下式得到。

其中，移量能从f是透镜的焦距，d和d是从PSD的像表面形成的光点的偏移。d和d的偏移量能从PSD的输出电压得到。从等式(1)和(2)推导出测量反射角

其中，其中△i=i-i。图4表明i/2m和d, drsquo;的差值在m=3和f=30mm。在图4中Delta;d=d-d。theta;的值依赖于光点在PSD上的移动。由于光点的亮度非常高，依靠PSD测量入射角对散射光不敏感。

图1 角度测量装置

图2 两束从平行平板反射的光和入射角放大

图3 用PSD测量入射角

图4 i/2m和光点偏移的关系

特别是，改进的干涉仪可用于高精度测量动态小范围角度变化。假定在图1中反射镜没有引入测量系统。而是让反射光束直接入射到平面平行板上的。根据参考[8]，角theta;(t)表示为

其中，lambda;是LD的中心波长，a (t)是干涉信号的相位，n, h分别是是折射率和平板的厚度。把等式(2)带入等式(4)，并且考虑到反射光的数量，最终得到角度测量的表达式

从公式(3)和(5)可以明显得出测量方案扩大了反射系数m。

图1中所描述的试验装置用来测量镜面的偏角和小范围角位移。在实验中，LD的中心波长lambda;为是660 nm。将PSD的位置分辨是2.1um, PSD表面图像的半个活动区域是17mm。n = 1.5163, h = 12mm, f = 30 mm, m = 3。反射光的数量可以通过观察反射镜上的反射光点来推测。让调制器将处于脱机状态。通过调整光学装置获得光束。测量目标如图5所示。加劲拉杆DE被固定在光学装置上。我们可以通过旋转千分尺头来使反射器发生偏转。偏转角度可以根据DE的长度和千分尺头的延伸长度来计算。DE的长度是149.5毫米和千分尺头的延伸长度是0.5mm。所以由千分尺头旋转产生的偏转角度，对应于3600旋转是3.34 times;10^-3rad。在反射器的偏转之前，第一次记录的在光敏PSD表面的光斑的偏移量d是3057.9um。千分尺头每次旋转360°，光斑的偏移量会产生相关的变化。图6 (a)是根据15次相关旋转所得到的偏角分别绘制的。图6 (b)表示根据等式(3)得到的测量结果。可以从图6 (c)中看出，图6 (a)和图6(b)的相应数据的差异很小。标准偏差的测量结果是1.7times;10^-4rad=35.1'。图6 (b)在光敏面上的光斑最大偏移量是13531.2um。在反射器的偏转之前，光斑的偏移量是3057.9um。根据等式(3)，theta;=5.37times;10^-2 rad=3.1°。根据等式.(3)可以通过减小反射系数增加偏转角度的测量范围。使用Eq.(3)，Delta;theta;的理论表达式为

其中△d=Delta;d =2.1um。在以上实验情况下，m=3时△A=3.1' .

图5 测量目标的装置

图6 (a)旋转次数和偏转角之间的关系;

(b)偏角的实际测量结果;

(c)偏角的测量误差

在图1中，当调制器按正弦方式更改LD输入电流调节波长lambda;^[9.10]，实验装置也可以被视为相位调制干涉仪。反射镜的引入实际上放大了从平面平行板反射的两束光光路的差别。图5中所示的固定在硬拉杆上的反射器仍被用作测量目标。在固定于杠杆DF的上的加硬拉杆B的一侧—固定在光学装置。一个压电式传感器(CPTZ)固定于开口端c和杆DF。 PZT由正弦信号驱动目的是让反射镜产生一个小的角位移。杆上点B和C之间的长度是147.2毫米。加在PZT的上的电压的振幅和频率分别是3.45 V和200Hz。因为PTZ产生的位移是85 nm/v。反光镜的角位移的振幅是1.992 times;10^-6rad。

在实验中，由于d的值是11912.9 um，平面平行板上初始入射角是0.378 rad。正弦调制频率是1 kHz。干涉信号a (t)由傅里叶变换计算^[11]。图7显示了角位移的实验曲线。实测的位移的频率是200 Hz。超过9个周期的正弦波的平均实测的位移的幅值是2.02010^-6rad。

图7 角位移的实验曲线

在同种情况下，上述测试在每隔几分钟的时间内重复了20次。在图8中，从连续测量获得的平均振幅的20个值很规则地出现在图8中。20个值的平均值是2.075 times; 10^-6rad.与计算值1.992 times;10^-6rad不同，平均幅值是8.3 times;10^-8rad。如果考虑实验中的一些类似于外部干扰的随机因素，这种错误的值表明实验结果反映了反射镜的真实角位移。二十个平均幅值的重复性标准差是5.5 times;10^-8rad，这比参考[8]所描述的2.7times;10^-7rad相比更小了。

图8 几分钟时间间隔内的20次

测量角位移平均幅值

总之，位置检测系统被纳入角度测量系统扩大了大测量范围。反射镜像的引入提高了动态角度测量的灵敏度和精度。实验结果表明可以测量约3。范围内的偏角。小角位移测量的重复性为5.5times;10^-8 rad。测量精度达到了约10^-8rad的数量级。方法的改进为角度测量提供了更广泛的应用，特别是在装配工艺和精确控制领域。

参考文献

[1] L. Kremer, D. Budelsky，D. Platte, and P. von Brentano, Appl. Opt. 34, 4827(1995).

[2] I. K. Ilev, Opt. Commun. 119, 513 (1995).

[3] M. Ikram and G. Hussain, Appl. Opt. 38, 113 (1999).

[4] J.-H. Zhang and C.-H. Menq, Meas. Sci. Technol. 10, 1247 (1999).

[5] P. S. Huang, S. Kiyono, and O. Kamada, Appl. Opt. 31, 6047 (1992).

[6] Yu. V. Filatov, D. P. Loukianov, and R. Probst, Metrologia 34, 343 (1997).

[7] R. Torroba and A. A. Tagliaferri, Opt. Commun. 149,213 (1998).

[8] C. Zhang and X. Wang, Opt. Eng. 43, 3008 (2004).

[9] Y. Liu, X. Wang, and X. Wang, Chin. Opt. Lett. 4, 309(2006).

[10] X. Wang, X. Wang, F. Qian, G. Chen, H. Lu, G. Chen, and Z. Fang, Chin. J

[11] O. Sasaki and H. Okazaki, Appl. Opt. 25, 3137 (1986).

剩余内容已隐藏，支付完成后下载完整资料

---

资料编号：[26636]，资料为PDF文档或Word文档，PDF文档可免费转换为Word