Preliminary Experiments on LAMDA Effect Microscopy

LAMDA效应显微镜的初步实验

• 批准号: 9014834
• 负责人: Alan Bearden
• 金额: $ 5万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1990
• 资助国家: 美国
• 起止时间: 1990-06-15 至 1991-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9014834&HistoricalAwards=false
• 关键词: Preliminary; Experiments; LAMDA; Effect; Microscopy

In a series of experiments during the summer of 1989 using laser interferometry to study auditory transduction and motion, the PIs observed that a small amount of light back-reflected into a He-Ne gas laser cavity by a moving object produced a large and predictable of the laser's output intensity. In company with many other laser experimentalist, the PIs at first deemed this observation as a chaotic nuisance effect to be avoided; further investigation showed that this effect can provide an extremely valuable alternative to complex, high-precision Michelson or MachZehnder or other types of interferometry. This new method, using only an inexpensive gas laser and the target, is particularly useful for the measurement of motions and displacements from microns down to picometers. The effect, named LAMDA (Laser Amplified Motion Detection and Analysis), is linear for changes in target position of less than 8 of the laser light wavelength and has been observed easily for motion as small as ~ 10 picometers. LAMDA requires only a small amount (106 - 0.1%) of back reflected light; this is easily obtained with diffuse scattering surfaces or from small changes of refractive index at dielectric boundaries. Although observed in the PI's laboratory with He-Ne lasers, the effect should be present for all continuous wave lasers including diode lasers. Being able to measure motion and displacement down to the picometer scale with the simplest of experimental arrangements, an inexpensive laser and the surface to be measured, opens a whole new range of motion and vibration analysis, imaging, optical metrology, and optical data-storage possibilities. 1 It is anticipated that LAMDA, when thoroughly understood and applied, will have an effect on many fields of scientific research and technology. For the past several months we have begun to characterize in detail the mechanism and provide a firm theoretical basis for this LAMDA effect. 2 To date, one of the most interesting applications of LAMDA that we have found so far is the possibility of using LAMDA's high z-resolution (picometers) as the basis for a light microscope having the ability to resolve finer detail than possible with normal Frauenhofer-diffraction limited microscope objectives (~200- 400nm). By utilizing the LAMDA effect in a scanning confocal microscope design, we hope to observe features of biological samples to a resolution of 10nm.

在1989年夏天用激光干涉术研究听觉传导和运动的一系列实验中，PI观察到，运动物体向He-Ne气体激光器腔内反向反射的少量光产生了大的和可预测的激光输出强度。与许多其他激光实验者一起，PI最初认为这种观测是一种需要避免的混乱滋扰效应；进一步的研究表明，这种效应可以提供一种非常有价值的替代复杂的、高精度的迈克尔逊或机械曾德或其他类型的干涉测量方法。这种新方法只使用廉价的气体激光器和靶子，特别适用于测量从微米到皮微米的运动和位移。这种效应被称为LAMDA(激光放大运动检测和分析)，对于小于8个激光波长的目标位置的变化是线性的，并且对于小到~10皮米的运动很容易观察到。Lamda只需要少量(106-0.1%)的背向反射光；这很容易通过漫反射表面或通过微小的介质边界折射率变化来获得。尽管在PI的实验室中观察到了He-Ne激光，但这种效应应该出现在包括二极管激光在内的所有连续波激光上。通过最简单的实验装置、廉价的激光器和待测表面，能够测量运动和位移到皮秒级，开辟了运动和振动分析、成像、光学计量学和光学数据存储的全新范围。1预计LAMD一旦得到彻底理解和应用，将对科学研究和技术的许多领域产生影响。在过去的几个月里，我们已经开始详细地描述这种LAMDA效应的机制，并为其提供了坚实的理论基础。2到目前为止，我们已经发现的LAMDA最有趣的应用之一是，有可能使用LAMDA的高z分辨率(皮秒)作为光学显微镜的基础，该光学显微镜具有比普通夫琅和费衍射限制显微镜物镜(~200-400 nm)更精细的分辨能力。通过在扫描共聚焦显微镜的设计中利用LAMDA效应，我们希望能够观察到10 nm分辨率的生物样品的特征。