Chinese English

A PROJECTION in which all angles around any point are correctly represented. In such a PROJECTION the SCALE is the same in all DIRECTIONS about any point. Very small shapes are correctly represented, resulting in an orthomorphic projection. Hence, the terms of 'confor­mal' and 'orthomorphic' are used synonymously since neither characteristic can exist independently of the other.

在该投影中，任何点周围的角度投影后无变形，同一点上任意方向的比例均相等，正形投影中形状保持不变。因此，“等角”和“正形”是同义词，二者的特性不能离开另外一个单独存在。

A PROJECTION produced by projecting the GEOGRAPHIC MERIDIANS and PARALLELS onto a cone which is tangent to (or intersects) the surface of a sphere, and then developing the cone into a plane.

A PROJECTION produced by pro­jecting the GEOGRAPHICAL MERIDIANS and PARALLELS onto a cylinder which is tangent to (or intersects) the sur­face of a sphere, and then developing the cylinder into a plane.

A PROJECTION having a constant area scale. Such a PROJECTION is not conformal and is not used for NAVIGATION. Also called equivalent pro­jection.

A PERSPECTIVE PROJECTION on a plane tangent to the surface of a sphere having the point of projection at the centre of the sphere. The PROJEC­TION is neither CONFORMAL nor EQUAL AREA. It is the only PROJECTION on which GREAT CIRCLES on the sphere are represented as straight lines. For this reason this PROJECTION is used principal­ly for CHARTS for GREAT CIRCLE SAILING.

一种在与某一球面相切的平面上的透视投影，投影点位于该球体的中心。该投影既不是正形投影，也不是等面积投影。它是球面大圆用大圆表示的唯一的一种投影。因此该投影主要用于大圆航法的海图。

The name given to the TRANSVERSE MERCATOR PROJEC­TION when the latter is extended right over both POLES. It is used for air charts of polar areas.

A CONFORMAL PRO­JEC­TION of the conical type, on which all GEOGRAPHIC MERI­DIANS are represented by straight lines which meet in a common point outside the limits of the MAP, and the GEOGRAPHIC PARALLELS are represented by a series of arcs of circles having this common point for a centre. MERIDIANS and PARALLELS intersect at right angles, and angles on the EARTH are correctly repre­sented on the PROJECTION. This PROJECTION may have one or two STAN­DARD PARALLELS along which the SCALE is held exact.

A CONFORMAL PROJECTION of the cylindrical type. The EQUATOR is represented by a straight line true to SCALE; the GEOGRAPHIC MERIDIANS are represented by parallel straight lines perpendicu­lar to the line representing the EQUATOR; they are spaced according to their distance apart at the EQUA­TOR. The GEOGRAPHIC PARALLELS are represented by a second system of straight lines perpendicular to the family of lines representing the MERIDIANS, and there­fore parallel with the EQUATOR. CONFORMALITY is achie­ved by mathematical analysis, the spacing of the PARAL­LELS being increased with the increasing distance from the EQUATOR to conform with the expanding SCALE along the PARALLELS resulting from the MERIDIANS being repre­sented by parallel lines. Since RHUMB LINES appear as straight lines and DIRECTIONS can be measured directly, this PROJECTION is widely used in NAVIGATI­ON.

一种圆柱型正形投影。其赤道由与实地相等的一条直线表示；其地理经线由与赤道相垂直的一系列平行直线表示；这些经线在赤道上的间距都相等。其地理纬线由与表示经线的线族相垂直的第二套直线系统表示，并且与赤道相平行。因此从数学分析可得到正形性。投影中各点处的长度比向任何方向都相等，纬线的间距随着距赤道距离增加而增加。由于等角航线被表示成直线并且可直接测定方向，所以该投影在航海中广为应用。

An OR­THOGRAPHIC PROJECTION having the plane of the projection parallel to the plane of some selected MERIDIAN; in this PRO­JECTION, the GEOGRAPHIC PARALLELS and the CENTRAL MERIDIAN are straight lines, the outer MERIDIAN is a full circle, and the other MERIDIANS are arcs of ellip­ses.

A perspective azimuthal PRO­JECTION in which the projecting lines, emanating from a point at infinity, are perpendicular to a tangent plane. This PROJECTION is used chiefly in NAUTICAL ASTRONOMY for interconverting COORDINATES of the CELE­STIAL EQUATOR and HORIZON systems.

由无穷远处的某点射出的投影线垂直于某一切面的透视方位投影。该投影主要用于航海天文学中天球赤道与地平坐标系的坐标转换。

The representation of a figure on a surface, either plane or curved, by means of project­ing lines emanating from a single point, which may be infinity. Also called geometric projection.

在平面或曲面上，通过可能位于无穷远处的某点发出的投影线，对某种形状进行的再现。亦称geometric projection（几何投影）。

An ORTHOGRAPHIC PROJEC­TION having the plane of the projection perpendicular to the AXIS of ROTATION of the EARTH (parallel with the plane of the EQUATOR); in this PROJECTION, the GEOGRA­PHIC MERIDIANS are straight lines.

A PROJECTION having the central GEOGRAPHIC MERIDIAN repre­sented by a straight line, along which the spacing for lines representing the GEOGRAPHIC PARALLELS is proportional to the distances apart of the PARALLELS; the PARALLELS are represented by arcs of circles which are not concentric, but whose centres lie on the line representing the CENTRAL MERI­DIAN, and whose radii are determined by the lengths of the elements of cones which are tangent along the PARALLELS. All MERIDIANS except the central one are curved. This PROJECTION is neither CONFORMAL nor EQUAL AREA but it has been widely used for MAPS of small areas because of the ease with which it can be con­structed.

一种投影，其中央经线表示为一条直线，在其上的地理纬线，其间距与各纬圈的间距成正比，各纬线为一系列圆弧，并不同心，但其中心处于由中央经线表示的直线上，并且其半径由相切于纬圈的圆锥元素的长度来确定。除中央经线外，其他经线都是曲线。该投影既不是正形投影，也不是等积投影，但由于它便于绘制，在小区域制图中广为应用。

Any standard PROJECTION used in MAP or CHART construction, which does not conform to a general north-south format with relation to the NEAT LINES of the MAP or CHART.

A PERSPECTIVE PROJECTION having the point of PROJECTION at the opposite end of the diameter of the sphere from the point of tangency of the plane of projection. It is conformal and is the only AZIMUTHAL PROJECTION having that quality. When the centre of the PROJECTION is located at a POLE of the sphere, it is called a stereographic polar projection; when on the EQUATOR, a stereographic meridional projection; and when on some other selected PARALLEL of LATITUDE, a stereographic horizon projection. Also called azimuthal orthomorphic projection.

一种透视投影，该投影点位于球体直径上与投影面切点相对的另一端。该投影为正形投影并具有该特征的唯一的一种方位投影。当投影中心位于球体的某一极点时，称作极球面投影；当投影中心位于赤道时，称作赤道球面投影；当投影中心位于其他所选定的地平纬圈时，称作地平球面投影。亦称azimuthal orthomorphic projection。

一种透视投影，该投影点位于球体直径上与投影面切点相对的另一端。该投影为正形投影并具有该特征的唯一的一种方位投影。当投影中心位于球体的某一极点时，称作极球面投影；当投影中心位于赤道时，称作赤道球面投影；当投影中心位于其他所选定的地平纬圈时，称作地平球面投影。亦称azimuthal orthomorphic projection。