Abstract
We have prepared a light‐focusing plastic rod, having a parabolic refractive‐index distribution, from a special and simple technique of diallyl isophthalate‐methyl methacrylate copolymerization. The internal transmission loss at 6328‐Å wavelength is 1.0 dB/m. The period of sine curved ray path through the rod and the constant of refractive‐index gradient are 50 mm and 0.0158 mm−2, respectively. The 13‐mm‐long 3.35‐mm‐diam rod functions as a lens with a 38 ° 54′ field angle.