| 摘要 |
<p>The reflector type lighting unit can be incorporated into systems, having a complete, or sectional mirror of ellipsoidal, parabolic or hyperbolic design with the light source at its focal point being of high intensity eg halogen, radium or mercury vapour type, has twin mirror sections constructed as parts of two ellipses with a common focal point, having a further focal point which together form the corners of a triangle with the light source situated either at the common focal point or at one of the others.</p> |
