2024年5月12日发(作者：电脑进不去系统一直在bios)

距离测量（Distance measurement）

距离测量

距离测量

测量地面上两点连线长度的工作。通常需要测定的是水平距离，即两

点连线投影在某水准面上的长度。它是确定地面点的平面位置的要素

之一。测量地面上两点连线长度的工作。测量工作中最基本的任务之

一。通常需要测定的是水平距离，即两点连线投影在某水准面上的长

度。距离测量的精度用相对精度表示，即距离测量的误差同该长度的

比值，用分子为1的分式1／N表示距离测量的方法有量尺量距、视

距测量、视差法测距和电磁波测距等，可根据测量的性质、精度要求

和其他条件选择。

编辑本段方式

量尺量距

用量尺直接测定两点间距离，分为钢尺量距和因瓦基线尺量距。钢尺

是用薄钢带制成，长20米、30米或50米。所量距离大于尺长时，

需先标定直线再分段测量。钢尺量距的精度一般高于1／1000。因瓦

基线尺是用温度膨胀系数很小的因瓦合金钢制造的线状尺或带状尺。

常用的线状尺长24米，钢丝直径1.65毫米，线尺两端各连接一个有

毫米刻划的分划尺，分划尺刻度为80毫米。量距时用10千克重锤通

过滑轮引张，使尺子成悬链线形状，线尺两端分划尺上同名刻划线间

的直线距离，即悬链线的弦长，是线尺的工作长度。因瓦基线尺受温

度变化影响极小，量距精度高达1／1000000、主要用于丈量三角网

的基线和其他高精度的边长。

视距测量

用有视距装置的测量仪器，按光学和三角学原理测定两点间距离的方

法。常用经纬仪、平板仪、水准仪和有刻划的标尺施测。通过望远镜

的两条视距丝，观测其在垂直竖立的标尺上的位置，视距丝在标尺上

的间隔称为尺间隔或视距读数，仪器到标尺间的距离是尺间隔的函数，

对于大多数仪器来说，在设计时使距离和尺间隔之比为100。视距测

量的精度可达／～／400 1 300 1。

视差法测距

用经纬仪测量定长基线横尺所对的水平角，利用三角公式计算仪器至

基线间的水平距离。此水平角称视差角。基线横尺两端固定标志间的

距离一般为2米。尺上装有水准器和瞄准器，以便将横尺安置水平并

使尺面与测线垂直。视差法测距的精度较低。

电磁波测距

新的理想的测距方法，测程较长，测距精度高，工作效率高。

距离测量

测量地面上两点连线长度的工作。通常需要测定的是水平距离，即两

点连线投影在某水准面上的长度。它是确定地面点的平面位置的要素

之一。在三角测量、导线测量、地形测量和工程测量等工作中都需要

进行距离测量。距离测量的精度用相对误差（相对精度）表示。即距

离测量的误差同该距离长度的比值，用分子为1的公式1 / N表示。

比值越小，距离测量的精度越高。距离测量常用的方法有量尺量距、

视距测量、视差法测距和电磁波测距等。

编辑本段双像视距装置

精

距离测量

度较高的一种视距测量装置。可用于低等级的导线测量。用光学方法

使标尺在望远镜视场中构成双像，这两个像错动的距离就是尺间隔。

由于尺间隔两端刻划靠在一起，加上测微装置就可以较精确地测量尺

间隔。为了减少大气折光的影响，标尺多由竖放改为横放。用双像视

距仪测量距离的精度较高，可达1 / 2000。有专用的双像视距仪，

但更多的是作为其他测量仪器的附加视距装置。

The optical wedge double sight range device is a wedge (Figure

2), which can be installed in the telescope of the other

measuring instruments and cover the part of the objective lens.

A horizontal or vertical scale is placed at the other end of

the measuring line. In the telescope field of view, the image

of the ruler can be seen through the optical wedge through the

objective lens and the image is not directly passed through the

objective lens through the wedge. Make a wedge angle of light

deflection but, thereby measuring the scale length of L.

According to the design of stadia constant equal to 100 or 200

integer request to decide but value. Some dual stadia can

automatically calculate the horizontal distance, and can

directly measure the horizontal distance. Some like two stadia

using a fixed length scale, and the light deflection angle but

is variable, measured by optical method varies with the

distance but angle, according to the triangle formula for

distance.

Edit this section no gauge sight meter

A sight meter that can measure distance without setting a scale

on a fixed point. Necessary measure distance angle value and

the length of baseline l were obtained but on the instrument.

Some stadia in scale but angle is fixed, the length of the

baseline with the measured distance changes (Figure 3). The non

metric stadia is mainly composed of a baseline ruler, a fixed

five angle prism, an optical wedge, an active five angle prism

with a index line and a telescope. In the selection of a target

point to be measured when the distance into the lens imaging

by optical wedge angle of refraction but, at the same time

without wedge into the refractive lens imaging. The moving five

angle prism can make the two images of the target coincide in

the field of view of the telescope. At this time, the index line

is intercepted on the baseline ruler L, and the distance is

multiplied by the sight line multiplication constant. Some

other instruments in the baseline length L is fixed, but with

the distance and angle change. The accuracy of measuring

distance with non metric stadia is poor, but it is very

convenient to measure distance from station to hill and cliff,

so it can be used for topographic mapping in undulating area.

A method of measuring the parallax angle of a short baseline

by using theodolite, and then calculating the horizontal

distance by trigonometric formula.

The length of short baseline is generally 1/10 to 1/100 of the

distance to be measured. Because the parallax angle measured

by theodolite is horizontal angle, the distance obtained by

parallax method is horizontal distance.

The method of calculating horizontal distance is called

baseline horizontal parallax method (Figure 4). The length of

the mark between the ends of the horizontal horizontal ruler

is B equal to 2 meters. The ruler has been accurately checked

and corrected, and the error is very small. Ruler is arranged

on the level and sight, so as to put the cross ruler to the

horizontal position, and the ruler surface and the line is

vertical. But after observing parallax angle, horizontal

distance calculation with the formula. The relative error of

the baseline horizontal parallax method is proportional to the

angle measurement error, and inversely proportional to the

angle of parallax. When the angle error is 1 ", but the angle

is about 33 '20", the relative accuracy of distance is 1/2000;

but when the angle is about 5 degrees 33', the relative accuracy

of 1/20000. If the parallax method is used to measure the long

distance, and the higher precision is required, more complex

parallax links must be arranged. The parallax segment is a

geometric figure consisting of baseline, parallax angle and

distance to be measured when parallax is used for ranging. The

distance to be measured can be measured by the baseline

horizontal parallax method, or the baseline baseline parallax

method is used to measure the short baselines of tens of meters

long, and then the large parallax links are used to obtain the

distance of hundreds of meters.

Edit this section of electromagnetic ranging

The electromagnetic range finder appeared in 1940s, and its

distance measurement, efficiency and accuracy are very high,

so the electromagnetic distance measurement has become an ideal

method of measuring distance.