focal length
美 
英
词形变化
复数：focal lengths
英汉双解
1. | 焦距the distance between the centre of a mirror or a lens and its focus |
英汉解释
英英解释
例句
Spot diameters of just a few thousands of an inch can readily be attained with convenient short focal length lenses.
用普通的短焦距透镜不难得到直径只有几十微米的光点。
The focal length you need depends on your distance from the burst and what you're trying to capture.
你所需要的焦距取决于你和被拍摄焰火间的距离，以及你想捕捉到怎样的画面。
Use angle encoder calibration coefficient of deviation of the long focal length of high-precision tracking system was satisfactory results.
利用编码器标定角偏差系数的方法，在长焦距高精度跟踪系统中获得了满意的效果。
Objective and the focal length of the specimen to be measured. The measurement of the size of the reticle.
十字线的像的尺寸取决于准直仪物镜的焦距和待测样品的焦距。
To determine power, divide the focal length of the telescope (in mm) by the focal length of the eyepiece (in mm).
将望远镜的焦距（单位：mm）除以目镜的焦距（单位：mm），就可以得到望远镜的放大率。
The focal length of the condensing lens should be such that the image of the source just fills the projecting lens.
聚光透镜的焦距应使光源的像正好照满放映透镜。
If you know the FOV, sensor size, and working distance, you can compute the focal length of the lens you need using the following formula.
如果你知道视野FOV，感应器大小，和工作距离，你能用以下之方程式去计算你所需之镜头的焦距。
It can be used to really evaluate the optical performance and imaging characters at any focal length of a zoom system.
可借助该程序对变焦系统任意焦距位置的光学性能和像差特性进行实时评估。
Using a longer focal length and photographing stars far from the north star increase the distance stars will move across the image.
使用长焦镜头拍摄远离北极星的星星，会增加星星在相片上移动轨迹。
Or, you can calculate the exit pupil by dividing the focal length of the eyepiece (in mm) by the focal ratio of the telescope.
或者，你还可以将目镜的焦距除以望远镜的焦比来得到出瞳尺寸。
These actually change the focal length of the lens rather than just magnifying the information that hits the sensor.
这些实际上改变了镜头的焦距而不是仅仅放大传感器采样数的信息资料。
The automatic adjustment in the focal length of the lens of the eye to permit retinal FOCUS of images of objects at varying distances.
眼调节眼睛瞳孔对焦距的自动调节，以获得不同距离的物体在视网膜上的成像
The more light pass through, the lower F number is. Shown in the following figure, F is the ration of focal length and effective diameter.
数值愈小表示通过的光量多，F数值是焦距长和有效开口的比值。
Focal length: The distance between the centre of a lens and its principal focus.
焦距：镜头中心与其主焦点的距离。
The longer the focal length of the telescope, generally the more power it has, the larger the image and the smaller the field of view.
一般来说，望远镜的焦距越长，它的放大率就越大，成像的尺寸就越大，但是视场范围就越小。
If you know the focal ratio but not the focal length, you can calculate it: focal length is the aperture (in mm) times the focal ratio.
如果你不知道焦距，只知道焦比（focalratio），你可以通过这样计算的得到焦距：孔径（单位是mm）乘以焦比就是焦距。
As the lens focal length is critical to capturing sharp images, this study aimed to develop a set of real-time auto-focus search algorithms.
基于镜头焦距对于撷取清晰影像有其重要性，故本研究旨在发展一套具有即时性之自动对焦搜寻演算法。
The aperture size (area of the aperture) of a lens could be calculated from focal length and the correspondent f-number.
光圈孔的大小，可从镜头的焦距与焦距比数中计算出来。
In taking a picture, the shutter, the focal length and the other things must be adjusted as the case may be .
在拍照过程中，快门、焦距等等必须按实际情况加以调整。
At present, some difficulties are encountered in measurement of long focal-length of mirrors.
目前，大口径长焦距反射镜焦距的精确测量存在很大难题。
Spot diameters of just a few thousands of an inch can readily be attained with convenient short focal length lenses.
用普通的短焦距透镜不难得到直径只有几十微米的光点。
On the basis of thin-lens focal length measurement experiment, the imaging law of refraction-reflection system was further studied.
在薄透镜焦距测定实验的基础上，进一步讨论了折射反射系统成像的规律。
Zooming optical system is a system in which the focal length can be changed continuously but the image surface position keeps stable.
变焦距光学系统是一种焦距可连续改变而像面位置保持稳定的光学系统。
The software computes the Back focal length from focal plane position and the reference position (as well as the offset, if entered).
软件根据焦面位置和参考位置（以及偏移量，如果有输入的话）来计算后焦距。
Z sitting on the bed, I am smiling camera position, at the lens, the focal length of the well, set up a regular.
Z坐在床上，我摆好相机的位置，对准镜头，对好焦距，设置了定时。
One zoom lens can replace several fixed focal-length lensed, but results are likely to be inferior.
一个变焦镜头可以代替多个固定焦矩镜头，但效果很可能比不上。
The lens is set to its widest focal length (38mm of the 35mm equivalent) and a polarizer is stacked on top of the 28mm UV filter.
镜头设置为最广泛的焦距（相当于38毫米的35毫米）和偏光是紫外线过滤堆积在上面的28毫米。
The easiest way to get a pleasing background is to use a long focal length and a wide aperture.
要想得到干净背景的最简单的方法就是使用长焦距和大光圈镜头，是背景虚化。
Object distance, image distance and focal length are distances, so they cannot be negative.
物距、像距与焦距都是距离，故也不可能为负数。
The focal length was found to be roughly proportional to the radius of the curvature.
发现焦距粗略地和曲率半径成正比。
Zoom lens A lens whose focal length can be varied continuously over a substantial range.
变焦镜头可以把焦矩在相当大的范围内连续改变的镜头。
This is the ratio of the focal length of the telescope to its aperture.
这是指望远镜的焦距与其孔径的比值。
For large aperture lens, scanning method was developed to measure the focal length in different locations within the mirror.
针对被测镜大口径的问题，采用了扫描的方法，这样可以测量被测镜不同位置的焦距。
You must first specify the focal length of the telescope and the size of the CCD chip or film negative.
您必须先指定望远镜的焦距，还有CCD晶片或底片的尺寸。
In order to be able to evaluate a large focal length range, different converter lenses must be used.
为了能够计算较大的焦距范围，根据焦距的大小必须使用不同的转换透镜。
The scanner's baseline correction including focal length adjustment and brightness, contrast and white balance, color, tuning, etc.
扫描仪的基准订侧包含焦距调度和平度、差比度、不暗不均、颜色调校等。
If very expensive, big, and heavy, may be almost as good and almost as fast at any given focal length as cheap fixed primes.
如果很贵，很大，很重，那么它几乎可以做到和那些等焦距廉价的定焦一样快和好。
On this basis, we calculated the camera's focal length and target depth information in the calibration test.
在此基础上进行了标定试验，计算出摄像机的焦距和标靶的深度信息；
It has just the right field of view and focal length to focus on your face at arm's length.
它只是角度和焦距的权利方面对你的脸上专注于手臂的长度。
Internal water passages eliminate outside cooling lines on multiple focal length configurations.
内部水通道，消除多倍焦距配置的外界冷却。
After many experiments on the scanner's focal length error which makes up his mind.
众次测验考试后，差扫描仪的焦距差错也不离心洋有数了。
