Optics is mainly to study the phenomenon of light, nature and application, including the interaction between light and matter, the production of optical instruments. Optics usually studies the physical behavior of infrared, ultraviolet and visible light. Because light is electromagnetic waves, other forms of electromagnetic radiation, such as X-ray, microwave, electromagnetic radiation and radio waves, also have similar light characteristics. Which geometric optics, describes the propagation of light, a lens, mirror and prism combination of the optical system, with geometric optics can explain the reflection, refraction and so on.
Magical Optical Aberration
The concave mirror in front of you will display your "inverted real image." Can this mirror-looking process show our "erect virtual image," though? It seems not! However, when you turn on the camera on your mobile phone and slowly approach the concave mirror, you will see an erect virtual image of yourself on your phone at a certain distance! When you see it, slowly move your mobile phone away, and you will see that the erect virtual image instantly becomes an inverted real image after passing a certain line. Can you infer the focus of this concave mirror by the point where this change occurs?
A Colorful Table of Geometric Optics
Press the button and you will see multiple lines of colorful laser beams. At the end in the front, smoke begins to be released, allowing you to see the routes of the laser beams. Now you can move the triangular and rectangular prisms and other lenses and mirrors to observe the various effects of geometrical optics, such as reflection, refraction, and diffraction. Think about this: why do you need smoke? What material is this ethereal fog made of? How is it produced?
Water Running Upward？
Everyone knows that water runs from high places to low places. However, in this exhibit, we see that water drops do not fall downward but go upward in the dim light. Why? Does it have anything to do with the flashing light? When we watch TV and movies, sometimes when a horse-drawn carriage moves forward, the wheels spin in a backward direction. It is the same reason with this exhibit: when you see something with a limited time frame and the intermittence is regular, you will see the illusion of something going backward.
Real Image and Virtual Image
Observe the concave mirror in front of you, and see whether your image in the mirror is erect or inverted. Is it a "real image" or a "virtual" one? Take a flashlight or turn on the light on your mobile phone. Shine the light on your forehead. Can you see a light dot on the forehead of the image? Shine the light on the forehead of the image. Does the same light dot appear on your forehead? The process helps us better understand the meaning of a "real image." Then, turn on the camera on your mobile phone and point it to the center of the concave mirror while slowly approaching it. You will see an erect image of yourself appearing on your phone. Is it a "real image" or a "virtual image"? Where does the image form? Slowly move your phone away, and you will see the erect image instantaneously becomes an inverted image after passing a certain "line." What is this "line"?