查询词典 aperture of lens

It is the ratio of the aperture diameter to the focal length of the lens.

经过选择的数字成一系列。

Based on the propagation law of partially coherent light, the spectral changes of Gaussian Schell-model beams passing through an astigmatic aperture lens are studied.

从部分相干光的传输理论出发，研究了高斯-谢尔模型光束通过光阑像散透镜传输轴上的光谱变化规律。

Eyepieces are differentiated by their '' field stop '', which is the narrowest aperture that light entering the eyepiece must pass through to reach the field lens of the eyepiece.

目镜由他们的''视野阑''做区分，这是进入目镜的光线抵达场透镜前所经过的最狭窄孔径。

The merit of the invention are: 1 adopting free curved surface imaging method , three part reflection type Zernike polynomial free curved surface forms short focal distance bigger, relative apertures bigger fields of view angle imaging , rectifying optical aberration much better and its structure is simple; 2 adopting the reflection structure without optical lens, has removed the effect of various chromatic aberration , guarantee the imaging articulation; 3 adopt the design of short focal distance big fields of view angle, focal distance 8 - 15 mm, field of view angles 100 -135 degree, having 120 times multiplications under 250 mm imaging distance, having ultra-thin characteristic property; 4 adopting big relative apertures design ,the relative aperture is 2.0-2.4, having improved the illuminance of flat surface; 5 adopting image space telecentric imaging method , ensures that the image surface irradiance is homogeneous.

本发明的优点是：1采用自由曲面成像方法，三片反射式Zernike多项式自由曲面形成短焦距大相对孔径大视场角成像，更好地校正像差，结构简单；2采用无透镜形式的反射式结构，消除了各种色差影响，保证成像清晰度；3采用短焦距大视场角设计，焦距8～15mm，具有100～135度的视场角，在250mm成像距离下有120倍的放大倍数，具有超薄特性；4采用大相对孔径设计，相对孔径为2.0～2.4，提高像平面上的光照度；5采用像方远心成像方法，保证像面辐照度均匀。

Based on the Fresnel diffraction integral and the complex Gaussian expansion for the hard-edge aperture function, a simple and analytical expression for calculating the diffraction field distribution of an apertured lens is presented.

基于菲涅尔衍射积分和将硬边孔径函数展开成有限项复高斯级数方法推导出了计算透镜衍射光强分布的解析表达式。

Fish eye lens is a kind of reversed telephoto lens having big relative aperture, large view angle and long back working length. Its view angle can reach 180 degree or even more so it can image object covering semisphere or larger than semisphere to limited plane.

鱼眼镜头是一种具有大相对孔径、大视场角和较长的后工作距离的反摄远镜头，它的视场角可以达到甚至超过180°，因此它能够将半球空域甚至超半球空域的物体成象在有限的象平面上。

A new type fiber coupling system is designed,which consists of four parts:large aperture lens,1/4 pitch grin lens,taper fiber and step optical fiber with spherical end surface.

设计了一种新型的耦合系统，该耦合系统由大口径聚焦透镜、1/4节距自聚焦透镜、锥形光纤和球端光纤四部分组成。

The all-purpose 2.8- to 12-millimeter IR varifocal lens provides the proper field of view for most surveillance applications. The 2.9- to 8.2-millimeter IR varifocal lens features aspherical optics to provide a fast F1.0 maximum aperture for best low-light performance.

多功能的2.8至12mm红外变焦镜头为大多数监视应用提供了适当的视场角。2.9至8.2mm红外变焦镜头以非球面光学为特色，为最佳低光性能提供了高速的F1.0最大光圈。

The ratio of the focal length of a lens or lens system to the effective diameter of its aperture.

屈光度透镜或棱镜折光率的一种量度，等于以米计算焦距之倒数

The ratio of the focal length of a lens or lens system to the effective diameter of its aperture.

找物镜调。。。相关的英文歌曲找物镜调。。。相关的英语测试到沙龙找物镜调。。。相关的帖子

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。