1, observe and record the focal length of the convex lens.
The purpose of determining the focal length of convex lens is to calculate the range of object distance and image distance by using the focal length of convex lens in the experiment. It is necessary to observe and record the focal length of the convex lens before starting the experiment. We can measure the distance from the light spot focused by the convex lens to the convex lens, which is the focal length of the convex lens.
2. Place the object beyond twice the focal length.
Putting an object out of the focal length of the convex lens is to make the object become an inverted and reduced real image in the convex lens. During the experiment, it is necessary to place the object at a position more than twice the focal length of the convex lens. By adjusting the distance between the object and the convex lens, the appropriate object distance can be found.
3. Move the screen to find a clear image
Moving the light curtain to find a clear image is the core step of the experiment, and it is also the expression form of the experimental results. After adjusting the object distance, you can find a clear image by moving the light screen. You need to pay attention to the position of the light screen to ensure that the light screen is in focus and the image is clearly visible. When the image is clear, we can observe the size, inversion and virtual reality of the image.
Application of convex lens
1, magnifying glass application
Convex lenses have the function of magnifying images of objects, so they are widely used to manufacture various optical instruments and equipment, such as microscopes and telescopes. Magnifier can also be used to observe small objects such as jewelry, antiques and printed matter, so as to better understand their details and characteristics.
2. Photography application
Convex lens plays an important role in photography. Photographers can use convex lenses to focus light and control the clarity of images. Convex lenses can also be used to make various optical instruments, such as cameras and video cameras, to shoot high-quality images and videos.
3. Medical application:
Convex lenses are also widely used in the medical field. For example, doctors can use convex lenses to observe patients' eyes, skin and other parts in order to better diagnose and treat diseases. Convex lenses can also be used to manufacture medical equipment, such as surgical microscopes and endoscopes, to improve the accuracy and safety of surgery.