convex and then concave lens in front of a light source, the light will be parallel but narrower than when it came in such as in a laser beam expander/compressor. Using a pen laser and a convex and concave lens, is it possible to focus the beam by putting a convex then a concave.....
Plano-convex lenses are plane on one side and convex on the other one. Also, it is possible to make biconvex lenses with different curvature radii on both sides. Similarly, defocusing lenses can be biconcave or plano-concave. Figure 4: Different types of optical lenses. According to lens...
However, we also need to consider the sign convention for the object distance. According to the sign convention, distances in front of the mirror are positive, and distances behind the mirror are negative. Therefore, the closer position is at 18 cm in front of the mirror (positive do), ...