Optics Terminology

1. when a material transmits some incident light but absorbs or reflects the rest; objects are not clearly seen through the material
3. an image that can be found by tracing real rays that emerge from an optical device backward to perceived or apparent origins
5. the changing of shape of the eye lens by eye muscles to allow a sharply focused image to form on the retina
10. the separation of white light into its constituent colours (i.e. colours of the rainbow)
11. reproduction of an object through the use of light
13. a transparent, gelatinous mass in the eye that plays an important role in providing metabolic nutrient requirements of the lens and acting like a shock absorber
14. a circular muscle with a hole in the middle that contracts and expands to control the amount of light that gets into the eye
15. the inability of the eye to focus light from near objects; far-sightedness
17. the depth that an object appears to be at, due to the refraction of light in a transparent medium
19. the perpendicular line to a mirror surface
20. a virtual image that forms as a result of refraction and total internal reflection in Earth’s atmosphere
21. an image that can be seen on a screen as a result of light rays actually arriving at the image location
23. the hole in the eye that allows light to enter

2. the bending or change in direction of light when it travels from one medium into another
4. type of photoreceptor cells in the retina which give us colour visions
6. the angle of incidence that results in an angle of refraction of 90°
7. to spread apart
8. any physical substance through which energy can be transferred
9. the point at the exact centre of the lens is known as the ___________ centre
12. the inability of the eye to focus light from distant objects; near-sightedness
16. a lens that is thickest in the middle and that causes incident parallel light rays to converge through a single point after refraction
18. a form of far-sightedness caused by a loss of accommodation as a person ages
22. the portion of eye at the center of the retina that processes sharp, clear, straight-ahead vision