| 摘要 |
A parabolic reflector is made of sheet material from a flat pliable elongated blank bent to form a parabolically curved shield shaped member. Both blank and member have continuously varying transverse widths from end to end thereof and terminate in a pointed lobe at one end or in two pointed lobes at opposite ends. Opposite lateral edges of the blank and member are oppositely curved. The blank and member are symmetrical on opposite sides of a central longitudinal line. The member is parabolically curved longitudinally from end to end and is straight transversely from end to end. The member can be formed by applying a force to the pointed end of single lobed blank while clamping the other end, or by applying equal forces to the pointed ends of a double lobed member. A plurality of parabolically curved members may be disposed side-by-side to increase the area of reflection. A plurality of double lobed members may be attached together at their centers and spread angularly apart to define a parabolic bowl.
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