Draw the optical path diagram of camera imaging, camera imaging and magnifying glass imaging.

1. Optical path diagram of camera imaging

This is a typical image of a camera. Let's have a look. It consists of three basic components of a camera.

camera bellows

camera lens

The sensor

Camera imaging actually uses the following two principles:

(1), the lens of the camera is equivalent to a convex lens, and the light emitted by the object passes through the lens of the camera and converges on the film to form an inverted and reduced real image.

(2) The photosensitive material (silver halide) is used, which is very sensitive to light and can form crystals with different sizes under the irradiation of light with different intensities. After coating this photosensitive material on a smooth board and exposing it for a period of time, images can be recorded.

2. Optical path diagram of camera imaging The lens of a camera can be regarded as a convex lens. The light emitted by the light source is converged on the projection negative after being acted by the spherical reflector and the condenser, and then an inverted magnified real image is formed in the plane mirror through the convex lens. The light path is changed by the plane mirror and reflected to the screen. When the object image of the convex lens is larger than one focal length and smaller than two focal lengths, the principle of inverting and magnifying the real image is adopted. (2f>u>f becomes an enlarged inverted image)

3. Optical path diagram of magnifying glass imaging

Note: f= focal length? F= focus

Extended data:

Regarding the law of convex lens imaging: 1, when the object distance is greater than 2 times the focal length, the image distance is between 1 times the focal length and 2 times the focal length, forming an inverted and reduced real image. At this point, the image distance is less than the object distance, the image is less than the object, and the object is opposite.

Application: camera, video camera.

2. When the object distance is equal to twice the focal length, the image distance is also twice the focal length, forming an inverted real image with equal size. At this time, the object distance is equal to the image distance, and the image is equal to the size of the object, and the object image is different.

Application: focal length measurement.

3. When the object distance is less than 2 times the focal length and greater than 1 times the focal length, the image distance is greater than 2 times the focal length, forming an inverted magnified real image. At this point, the image distance is greater than the object distance, the image is greater than the object, and the object is opposite.

Application: projector, slide projector, film projector.

4. When the object distance is equal to 1 times the focal length, it will not be imaged, but will be emitted as parallel light.

5. When the object distance is less than 1 times the focal length, it becomes a vertical magnified virtual image. At this point, the image distance is greater than the object distance, the image is greater than the object, and the object is on the same side.

Purpose: Magnifier.

6. When talking about the difference between real image and virtual image, we often use a formula: "The virtual image is on the same side, and the real image is on the opposite side".

References:

Baidu Encyclopedia —— The Law of Convex Lens Imaging