1. Chapter 16-2 Light and Matter

2. Color: the dispersion of white light into the color spectrum ROYGBIV

3. Newton did the first experiments demonstrating that white light contained all the colors in the spectrum

4. Light Transmission Terminology Transparent materials that transmit light waves without distorting images, e.g., glass Translucent materials that transmit light but do not permit objects to be seen clearly, e.g., tissue paper Opaque materials which transmit no light, e.g., brick

5. Color by Addition Primary Light Colors: Red, Blue, Green Secondary Light Colors: Magenta= red + blue Yellow = red + green Cyan = blue + green

6. Color by Addition

7. Color Addition

11. Color by Subtraction Primary pigments: absorb one primary color from white light: (yellow, cyan, magenta) and reflect two primary colors Secondary pigment: absorb two primary colors from white light: red, green blue Difference between dye and pigment: Dye-- a (molecule) that absorbs certain wavelengths of light, Pigment-- (particle)—colored material that absorbs certain wavelengths

12. Color by Subtraction

13. Thin Film Interference any film thickness equal to an odd multiple of quarter wavelengths will reinforce a given color. The spectrum of colors produced by an oil film on water is due to interference.

14. INCIDENT R1: Reflection from front side of soap: wave inverted R2 Reflection from back side of soap: not inverted

15. INCIDENT R1: Reflection from front side of soap: wave inverted R2 Reflection from back side of soap: not inverted

16. Polarization of Light Unpolarized light vibrates in all planes polarized light all vibrates in a particular plane

17. In a: only vertically polarized light is transmitted In b: only horizontally polarized light is transmitted

18. Polarization by Reflection Light reflecting off horizontal surfaces is horizontally polarized Vertically polarized sunglasses will cut down glare (filter out the horizontally polarized light)

19. End 16-2