采用模式变形反射镜的激光谐振腔象差的自适应校正

基于Ｚａｒｎｉｋｅ多项式的概念，提出了三自由度模式变形反射镜激光谐空象差的自适应校正原理，分析了系统开环传递函数和系统稳定性，闭环系统计算机模拟结果表明，该系统在频率为１０Ｈｚ以下的外界相位扰动的情况下，能校正９０％以上的动态象差。     

JC—1型精密测角仪光学系统设计

本文重点介绍JC-1型精密测角仪的动态光电自准直定位平行光管光学系统,为了满足测角仪对多谱线高精度测量的要求,应采用的结构形式及象差校正方案。     

通用单元控制器的研究

介绍了与ＦＭＳ／ＣＩＭＳ发展相适应的通用的单元控制器的开放体系结构，给出了一个不随具体环境而改变的通用单元控制器的设计方法和实现技术。这种新型的通用单元控制器正在被用来替代从国外进口的ＦＦＳ５００－２ ＦＭＳ控制器。     

新型 F·■镜头设计

本文论述了由多片分离弯月型透镜构成的 F·θ镜头,以及它在光焦度分配、象差校正、公差制定、成本分析等方面的设计工作。新型 F·θ镜头具有体积小、重量轻、使用普通光学材料、对制造误差灵敏的面数少等优点。     

亚微米i线投影光刻物镜的光学设计与研制

叙述亚微米投影光刻物镜光学设计要点：光刻分辨力Ｒ与波长λ、数值孔径ＮＡ的关系；光学系统双远心的构成方法；光刻物镜的象差校正优化设计中的需控目标值等问题。介绍一个亚微米ｉ线投影光刻物镜的设计结果、光学制造公差和质量控制方法，以及其主要性能测试结果。     

基于参数辨识的永磁同步电机自校正速度控制方法

针对永磁同步电机伺服系统的机械参数经常发生变化的情况,提出了一种通过辨识转动惯量和摩擦系数实现速度控制器系数自校正的方法.辨识转动惯量和摩擦系数采用的是根据波波夫超稳定理论设计的一种转动惯量和摩擦系数的模型参考辨识算法.辨识中引入了负载转矩观测器的观测值,使辨识算法不需要附加条件.参数辨识的结果用于速度控制器的校正.通过实验分析了速度环采用比例积分(PI)控制器时控制器的系数不等于理论计算值的问题,得出了一种简单的控制器系数自校正规律--比例系数和转动惯量成正比,且积分系数和摩擦系数也成正比.这种方法能够根据机械参数的变化校正控制器,提高速度控制的性能.仿真结果证明了参数辨识方法和控制器系数校正规律的有效性.     

改善高平均功率固体激光器光束质量的研究

本文首先概述了内含热透镜的激光谐振腔的分析方法，提出影响高平均功率固体激光器光束质量的主要因素是激光介质的热效应，尤其是非对称的热透镜象差。因此，改善光束质量的途径是补偿或修正透镜象差，使光束质量达到非相干多模振荡的理论值。     

全息剪切干涉法测量透镜几何象差

本文用全息双频光栅剪切干涉装置对透镜几何象差的测量进行实验研究。将象差光束中两剪切干涉光线的交点看成点源,提出了用经典杨氏干涉观点、由剪切条纹图确定这些交点的空间位置而直接得到几何象差的杨氏条纹分析法。对几个透镜的象差作了测量和分析;与设计理论值作比较,二者符合良好。     

透过封装材料来检验MEMS和MOEMS的表面特性

已经证实光学轮廓仪能成功地检验未封装MEMS器件的表面特性。可是，大部分器件必须在不同条件的封装之后，如真空、升高温度或其它特殊环境，才能做最终检验。文章描述了一种新型的干涉表面轮廓技术，用于在高倍率下透射封装介质来测量器件表面的特性。三项引入技术包括校正象差和长工作距离的物镜、有效照明系统、色散补偿技术。测试数据表明标准物镜和色散补偿物镜所测得的结果极为相近。     

同步发电机组自校正控制算法的并行处理

自校正控制已在不少工业对象中得到成功的应用。由于自校正控制算法需要较长的计算时间，使它在一些响应速度快的对象中的应用受到一定限制。本文针对同步发电机组转速与励磁的综合自校正稳定控制，提出一种并行处理算法，并设计了一种多ＣＰＵ控制器予以实现。模拟试验结果表明，它可大大提高运算速度，以满足实时控制的要求。     

Testing of Lagrange multiplier damped least-squares control algorithm for woofer-tweeter adaptive optics

A Lagrange multiplier-based damped least-squares control algorithm for woofer-tweeter (W-T) dual deformable-mirror (DM) adaptive optics (AO) is tested with a breadboard system. We show that the algorithm can complementarily command the two DMs to correct wavefront aberrations within a single optimization process: the woofer DM correcting the high-stroke, low-order aberrations, and the tweeter DM correcting the low-stroke, high-order aberrations. The optimal damping factor for a DM is found to be the median of the eigenvalue spectrum of the influence matrix of that DM. Wavefront control accuracy is maximized with the optimized control parameters. For the breadboard system, the residual wavefront error can be controlled to the precision of 0.03 μm in root mean square. The W-T dual-DM AO has applications in both ophthalmology and astronomy.     

Effect of rotation and translation on the expected benefit of an ideal method to correct the eye's higher-order aberrations

An ideal correcting method, such as a customized contact lens, laser refractive surgery, or adaptive optics, that corrects higher-order aberrations as well as defocus and astigmatism could improve vision. The benefit achieved with this ideal method will be limited by decentration. To estimate the significance of this potential limitation we studied the effect on image quality expected when an ideal correcting method translates or rotates with respect to the eye's pupil. Actual wave aberrations were obtained from ten human eyes for a 7.3-mm pupil with a Shack-Hartmann sensor. We computed the residual aberrations that appear as a result of translation or rotation of an otherwise ideal correction. The model is valid for adaptive optics, contact lenses, and phase plates, but it constitutes only a first approximation to the laser refractive surgery case where tissue removal occurs. Calculations suggest that the typical decentrations will reduce only slightly the optical benefits expected from an ideal correcting method. For typical decentrations the ideal correcting method offers a benefit in modulation 2-4 times higher (1.5-2 times in white light) than with a standard correction of defocus and astigmatism. We obtained analytical expressions that show the impact of translation and rotation on individual Zernike terms. These calculations also reveal which aberrations are most beneficial to correct. We provided practical rules to implement a selective correction depending on the amount of decentration. An experimental study was performed with an aberrated artificial eye corrected with an adaptive optics system, validating the theoretical predictions. The results in a keratoconic subject, also corrected with adaptive optics, showed that important benefits are obtained despite decentrations in highly aberrated eyes.     

Application of the pupil astigmatism criteria in optical design

We developed the pupil astigmatism criteria for correcting the quadratic field-dependent aberrations. These criteria provide an elegant way to determine and correct aberrations that have quadratic field dependence and arbitrary pupil dependence in the same way that the Abbe sine condition is used for aberrations with linear field dependence. Like the sine condition, the pupil astigmatism criteria involve only the properties of the rays originating from the on-axis object point, so it is convenient to implement them in optical design. We introduce an algorithm to apply the criteria in designing new well-corrected optical systems. Some example designs are presented.     

Optical traps with geometric aberrations

We assess the influence of geometric aberrations on the in-plane performance of optical traps by studying the dynamics of trapped colloidal spheres in deliberately distorted holographic optical tweezers. The lateral stiffness of the traps turns out to be insensitive to moderate amounts of coma, astigmatism, and spherical aberration. Moreover holographic aberration correction enables us to compensate inherent shortcomings in the optical train, thereby adaptively improving its performance. We also demonstrate the effects of geometric aberrations on the intensity profiles of optical vortices, whose readily measured deformations suggest a method for rapidly estimating and correcting geometric aberrations in holographic trapping systems.     

Effect of aberrations and scatter on image resolution assessed by adaptive optics retinal section imaging

The effect of increased high-order wavefront aberrations on image resolution was investigated, and the performance of adaptive optics (AO) for correcting wavefront error in the presence of increased light scatter was assessed in a model eye. An AO section imaging system provided an oblique view of a model retina and incorporated a wavefront sensor and deformable mirror for measurement and compensation of wavefront aberrations. Image resolution was quantified by the width of a Lorentzian curve fitted to a laser line image. Wavefront aberrations were significantly reduced with AO, resulting in improvement of image resolution. In the model eye, image resolution was degraded with increased high-order wavefront aberrations (horizontal coma and spherical) and improved with AO correction of wavefront error in the presence of increased light scatter. The findings of the current study suggest that AO imaging systems can potentially improve image resolution in aging eyes with increased aberrations and scatter.     

Wavefront-guided correction of ocular aberrations: are phase plate and refractive surgery solutions equal?

Wavefront-guided laser eye surgery has been recently introduced and holds the promise of correcting not only defocus and astigmatism in patients but also higher-order aberrations. Research is just beginning on the implementation of wavefront-guided methods in optical solutions, such as phase-plate-based spectacles, as alternatives to surgery. We investigate the theoretical differences between the implementation of wavefront-guided surgical and phase plate corrections. The residual aberrations of 43 model eyes are calculated after simulated refractive surgery and also after a phase plate is placed in front of the untreated eye. In each case, the current wavefront-guided paradigm that applies a direct map of the ocular aberrations to the correction zone is used. The simulation results demonstrate that an ablation map that is a Zernike fit of a direct transform of the ocular wavefront phase error is not as efficient in correcting refractive errors of sphere, cylinder, spherical aberration, and coma as when the same Zernike coefficients are applied to a phase plate, with statistically significant improvements from 2% to 6%.     

Inverse Convolution to Correction of Aberrations in Spectra Recorded with a Seya-Namioka Monochromator

Inverse convolution has been used to remove the effect of aberrations in the spectra recorded with a Seya-Namioka monochromator. The factors which affect the variation of the slit function with wavelength scanning are discussed. To suppress the effect of these factors, a simple method of the determination of the inverse convolver is given. The experimental results indicated that the inverse convolution provides a simple and very effective means of correcting the aberrations of a Seya-Namioka monochromator.     

Adaptive optics scanning laser ophthalmoscopy for in vivo imaging of lamina cribrosa

The lamina cribrosa has been postulated from in vitro studies as an early site of damage in glaucoma. Prior in vivo measures of laminar morphology have been confounded by ocular aberrations. In this study the lamina cribrosa was imaged after correcting for ocular aberrations using the adaptive optics scanning laser ophthalmoscope (AOSLO) in normal and glaucomatous eyes of rhesus monkeys. All measured laminar morphological parameters showed increased magnitudes in glaucomatous eyes relative to fellow control eyes, indicating altered structure. The AOSLO provides high-quality images of the lamina cribrosa and may have potential as a tool for early identification of glaucoma.     

Applications of short-coherence digital holography in microscopy

We present an optical system based on short-coherence digital holography suitable for the imaging of three-dimensional microscopic objects. The short temporal coherence properties of the light source allow optical sectioning of the sample. Proper reconstruction of different layers within biological samples is possible up to a depth of a few hundred micrometers, but multiple scattering and inhomogeneities in the refractive index reduce the imaging quality for deeper layers. We have studied the possibility of numerically correcting sample-induced aberrations, and we now propose a method of improving image quality. Numerical simulations and preliminary experimental results show that compensation of these aberrations is possible to some extent.     

Method for optimizing the correction of the eye's higher-order aberrations in the presence of decentrations.

The use of a correcting element to compensate for higher-order aberrations in an optical system often requires accurate alignment of the correcting element. This is not always possible, as in the case of a contact lens on the eye. We propose a method consisting of partial correction of every aberration term to minimize the average variance of the residual wave-front aberration produced by Gaussian decentrations (translations and rotations). Analytical expressions to estimate the fraction of every aberration term that should be corrected for a given amount of decentration are derived. To demonstrate the application of this method, three examples are used to compare performance with total and with partial correction. The partial correction is more robust and always yields some benefit regardless of the amount of decentration.