Ch-14-Thin Lenses.pptx
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This document summarizes the key differences between converging and diverging lenses. A converging lens is thicker in the center and bends light inward, while a diverging lens is thinner in the center and spreads light out. The focal length of a converging lens is real and positive, while the focal length of a diverging lens is virtual and negative. Key terms like optical center, principal axis, focal point, and focal length are also defined. Tables compare properties of converging and diverging lenses and explain short-sightedness and long-sightedness.
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2) The rules of reflection for curved mirrors, including that light rays parallel to the principal axis pass through the focal point.
3) How the position of the object determines the location and characteristics of the real or virtual image formed by concave and convex mirrors, such as whether images are upright or inverted and magnified or diminished.
Lecture 1: Basics of Lenses and Terminologies
This document discusses lenses and their properties. It begins by defining a lens as a transparent medium bounded by two curved surfaces that forms images by refracting light. The main types of lenses are then described as converging (convex) or diverging (concave). Various lens shapes and terminology are introduced, such as focal length and optical center. Properties of convex and concave lenses are explained. Thin lens approximation and sign conventions for lens calculations are also outlined. Finally, formulas are presented for determining the equivalent focal length of combinations of thin lenses.
Lens and Mirrors [Autosaved] for Grade 10.pptx
This document discusses the anatomy and properties of lenses and mirrors. It defines key terms like focal point, principal axis, radius of curvature, and types of lenses and mirrors. Ray diagrams are demonstrated as a technique for determining the characteristics of images formed by concave and convex mirrors and converging and diverging lenses based on the position of objects. Reflection and refraction principles are reviewed for understanding image formation.
Geometric-Optics.ppt
1) Geometric optics describes the behavior of light, including reflection off mirrors and refraction through lenses.
2) Mirrors can form real or virtual images depending on the position of the object. Concave mirrors form real images while convex mirrors form virtual images.
3) Lenses also form real or virtual images. Concave lenses form virtual images while convex lenses can form real images.
Lenses and and the parts
This document discusses different types of lenses, their properties, and applications. It defines converging and diverging lenses, and describes their focal lengths, principal axes, and how they form real or virtual images. Examples of optical instruments that use lenses are also provided, such as magnifying glasses, microscopes, and telescopes.
Convex Lens - A Complete Overview.PDF
A lens is a transparent material that concentrates or disperses light rays when it passes through them by refraction. According to the shape and purpose of the lens, they are classified into two types convex lens and concave lens. Let’s learn about convex lenses in detail in this article.
Light- refraction and reflection .pdf
1. Reflection is the bouncing back of light from a smooth surface, while refraction is the bending of light when passing from one medium to another.
2. Plane mirrors reflect light such that the angle of incidence equals the angle of reflection, forming virtual, upright images behind the mirror. Spherical mirrors like concave and convex mirrors can form real or virtual images depending on the position of the object.
3. Refraction follows Snell's law where the ratio of sines of the angle of incidence and refraction is a constant depending on the refractive indices of the two media. Lenses use refraction to form real images of objects.
Refraction of light in lenses
A lens is a transparent piece of glass with curved refracting surfaces that can be either convex or concave. Convex lenses are thicker in the middle and focus parallel rays of light to a focal point by converging the rays. Concave lenses are thinner in the middle and cause parallel rays of light to diverge as if originating from a focal point behind the lens. Lenses are used to either focus or diverge light depending on whether they are convex or concave.
Lenses
The document discusses the anatomy and properties of lenses. It explains that a lens is a piece of transparent material that refracts light in a way to form an image. There are two main types of lenses - converging and diverging lenses. Converging lenses bring parallel rays of light to a focal point, while diverging lenses spread them out. The document outlines key lens properties like focal length and principal axis, and provides rules for how light rays refract through converging and diverging lenses.
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Ch-14-Thin Lenses.pptx
- 2. Converging and diverging lenses . A converging (or convex) lens is thickest in the centre and bends light inwards The centre of a lens is its optical centre, C; the line through C at right angles to the lens is the principal axis. A diverging (or concave) lens is thinnest in the centre and spreads light out
- 3. S.No . Convex Lens Concave Lens 1. It has ability to converge light rays, so it is also Known as converging lens. It has ability to diverge light rays, so it is also Known as diverging lens. 2. It is thicker from the middle as compare to its edges. It is thinner from the middle as compare to its edges. 3. The image properties are dependent on “object distance”. The image properties are independent to “object distance”. 4. Its focal length (f) is real, so taken as positive. Its focal length (f) is virtual, so taken as negative.
- 4. Terms used in the study of lenses : Optical Center (C) : It is the midpoint between the surfaces of the lens on the principal axis. Note : Any ray passing through the optical center will not refract. Principal axis : It is the horizontal line passing through the optical center of the lens. Focal point ( F ) or ( principal focus ) : It is the point at which all rays parallel to the principal axis converge ( or appear to diverge, in case of diverging lens ) after refracting by the lens. Note : A lens has two focal points, one on each side of the lens. Focal length ( f ) : It is the distance between the optical center and the principal focus. Focal Plane : It is the plane that passes through the focal point and is perpendicular to the principal axis.
- 6. Ray diagrams https://phet.colorado.edu/sims/html/geometric- optics/latest/geometric-optics_en.html
- 8. https://phet.colorado.edu/sims/html/geometric- optics/latest/geometric-optics_en.html Convex lense, Diverging lense Use the simulator link to complete the table.
- 13. Short-Sightedness (or myopia) Long-Sightedness (or hyperopia) S.No. Short-Sightedness Long-Sightedness 1. Defect: In this defect person cannot see the far objects clearly. Defect: In this defect person can not see the near objects clearly. 2. Image Formation: In this defect the image is formed in front of retina. Image Formation: In this defect the image is formed behind the retina. 3. Correction : This defect can be corrected by using a concave lens of appropriate focal length. Correction: This defect can be corrected by using a convex lens of appropriate focal length.
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