the distance from a lens to its focus

a kind of new way to measure optical system focal distance automatically is proposed, which is based on ccd optical-electrical method and digital image processing method.

提出了一种基于ccd光电法和数字图像处理方法自动测量光学系统焦距的新方法。

a distance classifier to auto focus includes a distance-calculating module calculating a focal distance on the basis of blur levels of at least two images;

一种用于自动聚焦的距离分类器包括：距离计算模块，基于至少两个图像的模糊等级计算焦距；

moreover, applying the matrix method in the close axis optics leads directly to the expression of the focal distance of magnetic lens if the matrix is transmitted by the lens.

此外，应用类似于近轴光学中的矩阵方法，山磁透镜传输矩阵，直接导出了该磁透镜的焦距的表达式。

in this paper, the focal distance formula of lens in varied shapes is obtained by using object methods to make its physical meaning more obvious.

采用直观的方法得出了空气中各种形状的薄透镜的焦距公式，使其物理意义更加明显。

here the focal distance and both eyes parallax are absolute values which was measured by highly efficient sensor in one's eyes.

这就是我们两个眼球所测量得到的焦距和视差的绝对值。

but only with the right focal distance and correct aperture could we get the true pictures.

只有我们调对了焦距，对準了光圈，才有可能得到真实的图像。

this may avoid remedy mistake because of the actual different focal distance brings from as function.

这样可以避免as功能启动是由于实际的焦距不同带来的矫正错误。

comparing to see the objects with glasses, with seeing them directly will become bigger, equal or small all depends on focal distance between glasses and eyes.

戴眼镜看物体与眼睛直接看物体时相比，物体究竟变小、等大还是变大，取决于眼镜与眼睛光心之距与眼睛的焦距。

this text is to compare frensnel s zones plate with ordinary lens, on the axle point of light intension and focal distance as well as their difference in use.

当光通过菲涅耳半波带与普通透镜时，可发现在轴上点的光强、焦距以及用途上的不同。

the authors have reported two methods for measuring the efficient focal distance of the laser rod lenses.

提出几种计算和测量激光棒负透镜等效焦距的方法。

the major photographic conditions are tube voltage, which relates to the thickness of seed and exposure value, which based on the tube voltage, focal distance and sensitive material.

摄影条件主要取决于管电压和曝光值，管电压与种子厚度有关，曝光值则依管电压、焦片距和感光材料不同而异；

a slide lever on the bridge of the eyeglasses pushes the fluid forward or backward to alter the shape of that membrane, changing the focal distance depending on what the user is doing.

在眼镜横梁上的滑动控制桿推动流体向前或向后，以改变那层薄膜的形状，从而根据用户当前的动作来调整焦距。

when using it, one end is plugged into the water to adjust the focal distance of the telescope, a fisher man can watch the moving state of fish.

使用时将观鱼镜的一端插入水中，调节单筒望远镜的焦距，钓鱼者在岸上就可以观察到鱼在水中的活动情况。

from the focal distance formula of thin lens, the convergence and divergence nature of each kind of thin lens are discussed in different media.

从薄透镜的焦距公式出发，讨论了各种透镜在不同介质中的会聚与发散性质。

conjugate method is an accurate, simple and convenient method to measure the focal distance of thin convex lens.

共轭法是一种较为準确和简便的测量薄透镜焦距的方法。

based on lau effect in double grating, the focal distance of lens is measured.

根据计量光栅的特点，可以利用双光栅效应测量透镜焦距。

one major problem the researchers had to overcome was the fact that the human eye, with its minimum focal distance of several centimetres, cannot resolve objects on a contact lens.

研究人员必须解决的一个重要的问题是，人眼的最小焦距是几厘米，无法分辨出隐形眼镜上显示的物体。

an experimental investigation of the combination of a long focal distance bragg-fresnel lens with a bimorph mirror is described.

描述了对长焦距布拉格-菲涅耳透镜与可变曲率半径反射镜组合所做的实验研究。

abstract: the rules of ganssian light beams extended by lens are disscussed firstey and the relation between the optimum waist extended and focal distance of the lens are found out.

文摘：首次讨论了用透镜来扩展高斯光束的一般规律，找出了最佳扩展束腰与透镜焦距的关系。

this paper introduces a method for the measurement of stress of thin film. in this method a long focal distance microscope is used and deformation of the thin film on thin glass sheet is observed.

本文介绍一种利用长焦距显微镜观察玻璃薄片由镀膜淀积引起的形变来测量薄膜应力的方法。

correct under the guiding of route we successfully design and have trial-produced the one kind of new long large-scale camera of focal distance .

在正确路线的指引下，我们成功地设计和试制了一种新型长焦距大型照相机。

in measuring the focal distance of lens, the experimental accuracy is often affected by the poor quality in the formation of images.

在测量透镜焦距时，往往由于成像质量差而影响实验的精度。