Optics
The study of optics is the study of light. The most important source of energy is the sun, a natural source unlike a candle or a light bulb; they are artificial sources. Light shows various images by reflecting, transmitting, absorbing or refracting; without these properties of light, we could not see anything. Digicams and other optical devices use light, and mirrors or lenses to carry out a function, thus is a virtual image unlike real images. Light is also the reason why we see colours. It has no mass but we can feel the effects of light on matter. Therefore light is a source of energy.
Sources of energy that give off their own light are called luminous, like moons. The different forms of input energy are chemical, electrical, nuclear and thermal energy. Incanscendant light bulb is an examble of thermal energy, one that creates heat. Chemical energy could be a battery that provides light energy for a flashlight. Other emitting processes are phosphorenscene, electronicaldischarges (lightning), fluorescence, chemiluminescence, and bioluminescence where some living things like fish, basteria, squid and fugi emit light.
Images
An image is the likeness of an object and an otical device produces an image of an object. A real image can be placed on the screen. A virtual can not be placed on a screen; it can be seen only by looking at or through an optical device. Salt, Attitude, location, type are the characteristics of images.
An incident ray is a ray of lihght that travels toward a reflecting surface, The angle of incidence is the angle between the incident ray and the normal. The normal is the line drawn from the point of incidence at 90 degrees to the surface of the optical device. The reflected ray is the ray of light that bounces off a reflecting surface. The angle of reflection is the angle between the reflected ray and normal. The point of incidence is the spot where the incident ray strikes the reflecting surface. Otherwords, the incident ray is the original, the normal is perfectly the invisible line between the incident and reflected, and the reflected ray is the ray of the incident but reflected off the normal.
There are 2 lawys of reflection:
1. Angle of incidence is equal to the angle of reflection.
2. Incident ray, normal and reflected ray all lie on the same plane.