Ключевые слова: abstract, angle, beam of light, beams of light, breaking, bright, business, class, college, concept, convergent, convex, dark, design, direction, divergent, education, effect, electromagnetic, energy, equipment, focal point, glass, illumination, illustrative, industrial, industry, instrument, lab, laboratory, lamp, law, learning, lens, light beam, material, modern, nature, old, optical, optics, pattern, physics, prism, rays of light, refraction, science, spectrum, style, technology,