英语翻译A light screen device for measuring the velocity of a pr

英语翻译
A light screen device for measuring the velocity of a projectile comprising a laser disposed opposite to one end of a first plane reflecting mirror and inclined with respect thereto to cause a laser beam to strike the first plane reflecting mirror and in turn to reflect the beam to a second plane mirror and successively reflecting the beam back and forth vertically to higher points on each mirror surface forming a criss-cross rectangularly shaped light grid network therebetween.A light detector is disposed axially in line with a reflected beam to intercept and detect the continuing presence thereof and to generate a pulse signal in response to the projectile passing through the light screen to stop a counting circuit.
LASER SCREEN GOVERNMENTAL INTEREST
The invention described herein may be manufactured,used and licensed by or for the Government for governmental purposes without the payment to us of any royalty thereon.
Various means have been used in the prior art to determine the velocity of projectiles undergoing development.Some prior art devices utilize large wire coils to insure the clearance of a magnetized projectile passing therethrough.Frequently these large coils had the problem of generating a reduced induced pulse signal.The small pulse signal necessitated the use of more powerful magnets within the projectile to produce a signal capable of being adequately measured.In cases where the projectile being tested was small,it was not possible to change the size of the permanent magnet contained therein.The problem with prior art devices utilizing the break paper technique frequently required a thicker or more supportive arrangement to stop flexing and vibration of the paper by the wind.These large sheets of break paper generally cut down the availability of down range camera coverage of the projectile firing.

这是一种利用激光测量弹丸速度的轻丝网装置,其工作原理是：两块反射镜面对放置,当激光斜射在第一面水平的反射镜上,激光会折射到第二块水平的反射镜上,并以此继续垂直反射回更高的镜子表面,然后在两块水平反射镜之间形成纵横交织的激光网.一个光探测器沿着符合反射光束线路检查,持续地截取并进行检测,当回应的弹丸经过轻丝网时生成一个脉冲信号以停止计数电路.
政府的利益---激光屏
文中提到的发明的生产,使用,并没有得到政府和政府给的皇室的许可.
在先前技术发展的基础上,已经使用各种不同的方法来确定射弹的速度.有的利用现有技术设备的大型电线圈,以确保被磁化的弹丸经过时被消除磁化.但是用这种方法,会频繁出现减少脉冲信号的状况.对于这种很小的脉冲信号却需要弹丸在更强大的磁铁中被充分的测量.然而磁铁大小是不可能永远保持不变的.这个问题同先前频繁要求用更粗或者能更好的支持阻止风对纸的振动和扭曲而打破纸的技术一样.这些用于打穿的纸却在一般情况下会降低射击时照相机照相的覆盖范围.