透视规的研制

RESEARCH ON THE PERSPECTIVE INSTRUMENT

根据透视线在同一方向上两对应点间的距离之比为定值的结论而设计的透视规，是由３片两端带有针状尖端的长条板而构成，相互用铰链相连。３片长条板在一定力的作用下可绕铰链旋转，但停于任一位置后不会轻易转动。该仪器可迅速、准确地绘制灭点远离图板的透视线。文中进行了理论推导，并对结构设计、使用方法等作了叙述。

According to the rate being a fixed value of perspective line at two points on the same way,a perspective instrument has been designed. It consisted of three gear boards with pin shape at the two ends. The three boards were connected by feather joint and could turn at the action of force. They could not turn when stop at any position.It can be used quickly and accuratly to draw viewoiont which is far from perspective line.The theory derivation,constructure design and using method have been introduced at the paper.