Apparatus for producing a spherical pattern of light and method of manufacture

A process for manufacturing an apparatus for radiating light of sufficient intensity to cause photodynamic effects in an approximately uniform spherical pattern of approximately 4.pi. steradians comprising the steps of:

• (a) removing the cladding and sheathing from a region at one end of an optical fiber;
• (b) polishing the smooth, exposed end of the core of said optical fiber exposed by said removal of said cladding and sheathing, making a reasonably smooth, flat surface thereon;
• (c) coating said exposed core and said cladding and sheathing adjacent thereto with a light-scattering medium comprising an approximately equal mixture of powdered quartz and an optical adhesive curable by exposure to ultraviolet radiation, said light-scattering medium applied so as to have uniform scattering power in a spherical pattern around said exposed core and approximately centered thereon by means of the sub-steps;
• (c-i) launching laser light into said optical fiber at the end opposite that end being coated, said light being of sufficient intensity to produce visible rays emanating from the region being coated;
• (c-ii) coating said exposed core region with said light-scattering medium in an approximately spherical light scattering density as determined by an observed uniform intensity in said laser light in a spherical pattern surrounding said core;
• (c-iii) curing said applied coating by exposure to ultraviolet radiation;
• (c-iv) applying a plurality of additional layers of said light-scattering medium by repeating sub-steps (c-ii) and (c-iii).