公开(公告)号：US3849698A

公开(公告)日：1974-11-19

申请号：US35423773

申请日：1973-04-25

Applicant: STANFORD RESEARCH INST

Inventor： FROHBACH H

IPC: H04N5/06 ,  G01S7/52 ,  H03K4/06 ,  H01J29/70

CPC classification number: G01S7/52057 ,  H03K4/06

Abstract: An electrical waveform is generated which is sinusoidal relative to the angular position of a shaft which rotates in a single direction by means of an optically sensed, or scanned, patterned disk affixed to the shaft to rotate in synchronism with it. The pattern on the disk primarily comprises uniformly spaced parallel lines on its face. In addition, a half revolution sensor such as a peripheral band having halves of differing optical properties is used. A first photocell scans the lines on the disk as it is rotated to count the number of lines and a second photocell scans the half revolution indicator, e.g., the peripheral band (outside track) of the disk. The first photocell produces a series of pulses indicative of the number of lines scanned and the second photocell produces an output which indicates when all of the lines on the face have been counted once and provides interlace between alternate counts. The number of lines scanned is added until they have all been counted once to produce the increasing half of the sinusoidal wave and then they are subtracted until they have all been counted a second time to produce the decreasing half of the sinusoidal wave. The sequence is repeated continuously to provide the desired waveform which is used as the vertical deflection voltage for a display device. Each line counted is also used to generate a horizontal sweep voltage for the display device so that in spite of the sinusoidal character of the vertical deflection, the lines composing the raster of the display are evenly and uniformly spaced.

Abstract translation: 产生电波形，其相对于通过光学感测或扫描的图案化盘在单个方向上旋转的轴的角位置是正弦的，该盘固定到轴上以与其同步旋转。 盘上的图案主要包括在其表面上均匀间隔开的平行线。 此外，使用半旋转传感器，例如具有不同光学性质的一半的周边带。 第一光电管在旋转时扫描盘上的线以计数线数，而第二光电管元件扫描半转指示器，例如盘的外围带（外轨道）。 第一个光电管产生一系列指示被扫描线的数量的脉冲，而第二光电管产生一个输出，该输出指示何时所有的线上的线已被计数一次，并提供交替计数之间的交错。 扫描的行数被添加，直到它们全部被计数一次以产生正弦波的增加的一半，然后将它们减去，直到它们全部被计数第二次以产生正弦波的减小的一半。 连续重复该顺序以提供用作显示装置的垂直偏转电压的期望波形。 所计算的每一行也用于产生用于显示装置的水平扫描电压，使得即使垂直偏转的正弦曲线，构成显示器的光栅的线也均匀均匀地间隔开。