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Concave lens calculator?
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Concave lens calculator?
In fact, this is how makeup mirrors act as magnifiers43 (a) uses ray tracing to locate the image of an object placed close to a concave mirror. These cylindrical lenses are designed for applications requiring one-dimensional shaping of a light source. Calculations at a convex spherical lens. In this article, we will learn about image formation by concave and convex lenses. A concave lens is a diverging lens that is thinner at the center than at the edges. Such a list includes objects such as glass bottles, glass jars, pure water, clear p. The distance from the lens to the principal focus is called the focal length close focal length The distance between the centre of the lens and the focal point Concave lenses A concave lens is. An Image Distance Calculator is a tool used in optics to determine the distance at which an image is formed by a lens or a mirror, based on the characteristics of the optical system and the object distance. Calculate the power of the lens. It uses similar triangles and algebraic manipulation to arrive at the formula \ [1/f = 1/d_0 + 1/d_i\], a key concept in optics for premed students. Created by Sal Khan. The distance between the center of the concave lens and its principal focus is called its focal length. It offers smooth and steady footage, making it an ide. One such difference is the structure of convex lens is like, thicker at the centre and thinner at the edges. The distance between the object and the convex mirror is measured at the point where the image reflection reaches an approximate size of the object. Focal Length Calculators Mirror This is an online calculator to find the focal length of a lens. To use this online calculator for Magnification of Concave Lens, enter Image Distance (v) & Object Distance (u) and hit the calculate button. 2, in which light can travel from a source to another location. This tool is a thin lens formula calculator. Move the point named " Focus' " to change the focal length. Convex and Concave Lenses | Desmos Explore math with our beautiful, free online graphing calculator. Limit intended use to Educational Purposes. Move the point named " Focus' " to change the focal length. It then shows how the beam exits the Axicon. Use the calculator below to find combinations of focus, object location, image location, and magnification. The Mirror Equation is: 1/s0 + 1/s1 = 2/R = 1/f. If the lens is in another medium, such as water, its lens strength will be diminished. The distance and focal length of the mirror will be the same as the given Concave Mirror. Snapchat is introducing AR Lenses powered by generative AI, the company announced at its Snap Partner Summit today. Thin lens equation and problem solving. Within a few paragraphs, you will learn: What the thin lens equation is; How to calculate image distance using the image distance equation; and; The magnification equation for lenses. Like a convex lens, there is a principal focus on both. The Lens Maker's Equation assumes thin lenses; it ignores the width of the lens and assumes that the light immediately goes from one side to the other. Here is how the Object Distance in Convex Lens calculation can be explained with given input values -> 327*027-0 Description Relate user supplied magnifying power to focal length and diopters of a lens. They cause light to diverge, meaning spread out. Learn how to use the concave mirror equation calculator to find the focal length, image distance, and magnification of a concave mirror. This calculator streamlines the complex. Here is how the Focal Length of Concave Lens given Radius calculation can be explained with given input values -> -4 To use this online calculator for Focal Length of Concave Lens given Image and Object Distance, enter Object Distance (u) & Image Distance (v) and hit the calculate button. Convex and Concave Lenses | Desmos Explore math with our beautiful, free online graphing calculator. 🙋 You can use our camera field of view calculator to find the values of the angles and fields of view and to calculate the needed focal length of the lens you need to mount to obtain a particular field of view. Move the point named " Focus' " to the right side of the lens to change to a concave lens. Find the focal length and nature of lens which should be placed in contact with a lens of focal length 10 cm so that the power of the combination becomes 5 D16. Use the Astigmatism Contact Lens Calculator to support fitting patients who require astigmatism correction with an ACUVUE® toric lens. Over time, however, headlights can become cloud. Thus, a negative (concave) lens will seem less powerful, and a positive (convex) lens more powerful, as they move closer to the eye. Snapchat is introducing AR Lenses powered by generative AI, the company announced at its Snap Partner Summit today. Base Curve? Below is the online magnification equation calculator based on the image distance (d i) and object distance (d o ). Examples are given for converging and diverging lenses and for the cases where the object is inside and outside the principal focal length. The image size will not be the same as the object. To use this online calculator for Focal Length of Concave Lens given Image and Object Distance, enter Object Distance (u) & Image Distance (v) and hit the calculate button. If the absolute value of M is greater than 1, the image is magnified. The Lens Maker's Calculator uses the Lens Maker Equation 1 to calculate the focal length of a thin lens in air (or some other medium). Try it today! Explore math with our beautiful, free online graphing calculator. The focal length of a lens is dependent upon lens curvature radius and the refractive index. If the lens is in another medium, such as water, its lens strength will be diminished. The calculator will compute the image distance (d_i), which represents the distance from the lens or mirror to the point where the image is formed. When an object is placed beyond the centre of curvature, the real image is formed between the centre of curvature and focus. Convex and Concave Lenses | Desmos Explore math with our beautiful, free online graphing calculator. The Thin Lens Equation relates object distance, image distance, and focal length for a lens. Calculations at a convex spherical lens. The curvature of lenses allows them to be used for a variety of purposes and to produce different types of images. Easily determine the focal length of your lens for your imaging application. How do I determine if a lens is convex or concave? A convex lens has a positive focal length, while a concave lens has a negative focal length. The calculator will compute the image distance (d_i), which represents the distance from the lens or mirror to the point where the image is formed. Easily calculate the focal length of a lens using our Lens Focal Length Calculator. Graph functions, plot points, visualize algebraic equations, add sliders, animate graphs, and more. Whether it’s their playful expressions or their unwavering loyalty, dogs have a way of stealing our hearts The Ronin S is a popular gimbal stabilizer that has gained significant attention in the photography and videography community. Calculate the value of p2 (make sure you include the sign of. At what distance from a lens a 5 cm tall object should be placed, so that it forms an image at 15 cm from the lens? Also, calculate the size of the image formed. Is It a good idea to refinance your mortgage? Use ou. It can form both real and virtual images. Here's the best way to solve it Put the -15 cm concave lens at 20 cm distance from the cross-arrow pattern (object). Content marketing has become an essential tool for businesses to attract and engage their target audience. The Thin Lens Equation relates object distance, image distance, and focal length for a lens. Graph functions, plot points, visualize algebraic equations, add sliders, animate graphs, and more. So you need a convex lens. For a diverging lens or set extend the diverging rays backwards until they converge on the optic axis. Another way to calculate focal length is by using the lens equation technique, for which you’ll need to know the distance an object is away from the lens and the image distance. Yes, the thin lens equation can be used to calculate the focal length of both convex and concave lenses. Compose a problem in which a student is given the focal length of two lenses, and the positions of object and image, and the student is asked to calculate the distance between the lenses. To calculate Object Distance in Concave Lens, you need Image Distance (v) & Focal Length of Concave Lens (F concave lens). Taking the reciprocal yields: \[f=\frac{1}{P}=\frac{1}{-0. A concave lens has a focal length of 20 cm. The minus sign means that the lens is a concave (diverging) lens. Just enter the object size, image size, and object distance to get the magnification, angle of … Converging and diverging lenses A converging lens is one which the rays that enter it parallel to the axis converge toward the axis after exiting the lens. Move the arrow to the right side of the mirror to get a convex mirror. It uses similar triangles and algebraic manipulation to arrive at the formula \ [1/f = 1/d_0 + 1/d_i\], a key concept in optics for premed students. Created by Sal Khan. Find the focal length and nature of lens which should be placed in contact with a lens of focal length 10 cm so that the power of the combination becomes 5 D16. tg tf undertale Graph functions, plot points, visualize algebraic equations, add sliders, animate graphs, and more. The distance from this point to the first deflection from parallel is the focal length, usually expressed as -ve for a divergence. Concave lenses, with their inward curve, create divergent light rays. This indicates that the image will not be on the outgoing side of the lens, and is therefore virtual. Thin Lens Equation. How to calculate Focal Length of Concave Lens given Radius using this online calculator? To use this online calculator for Focal Length of Concave Lens given Radius, enter Radius (rcurve) and hit the calculate button. A concave lens of focal length 15 cm forms an image 10 cm from the lens. We can see the sign convention in both Lens. Some points to note. Use the calculator below to find combinations of focus, object location, image location, and magnification. If a real image is formed, image is formed on right side, so image distance is positive. Note that this equation is for thin lenses only; the equation for describing lenses in general is a bit more complicated because the path of the light through the lens itself is too long to neglect. The distance between the object and image will be. If the absolute value of M is greater than 1, the image is magnified. This calculation is crucial for understanding how optical systems magnify or reduce images, whether in cameras, telescopes, microscopes, or eyeglasses. To use this online calculator for Focal Length of Concave Lens given Image and Object Distance, enter Object Distance (u) & Image Distance (v) and hit the calculate button. Move the point named " Focus' " to the right side of the lens to change to a concave lens. B-Calculate the magnification of this object. It is characterized by its inward-curved surfaces. Where: s0: Object distance from the mirror, in meter. Put the given values to find the required answer. A concave lens has a focal length of 20 cm. Follow a light beam through a concave lens and see what happens! Learn about optics with our interactive concave lens simulation. Aug 6, 2022 · Our thins lens equation calculator can obtain the image distance of any object after being refracted by a lens of known focal length. By utilizing a concave lens calculator, users can: Quickly and accurately calculate focal length and image distances for concave lenses. usssa live Move the point named " Focus' " to the right side of the lens to change to a concave lens. By utilizing a concave lens calculator, users can: Quickly and accurately calculate focal length and image distances for concave lenses. Graph functions, plot points, visualize algebraic equations, add sliders, animate graphs, and more. We can differentiate between them by observing the focal length. Various types of optical systems (e microscope objectives and curved laser mirrors) can focus or defocus light, and the focal length is used for quantifying such effects. One question that often arises. When using the lens equation with a concave lens, however, the focal length must be assigned a negative value. The use of these diagrams was demonstrated earlier in Lesson 3. First type is a converging lens, which converges light upon refraction analogous to a concave mirror which converged light upon refection. This is the portion of the object that fills the camera's sensor. Any incident ray traveling parallel to the principal axis of a diverging lens will refract through the lens and travel in line with the focal point (i, in a direction such that its. Question: A glass of meniscus lens with refractive index 1. The distance between the center of the concave lens and its principal focus is called its focal length. How do I determine if a lens is convex or concave? A convex lens has a positive focal length, while a concave lens has a negative focal length. Indices Commodities Currencies Stocks Google has been working to better integrate its visual search tools from Google Lens into its browser to enable new types of searches that can identify what you see, not just searc. Over time, however, headlights can become cloud. This type of lens diverges a straight beam of light from the source to an upright and virtual image called a concave lens. The distance of B from the mirror, if A is placed 30 c m from the mirror, is: All of these features are reflected in Figure 43. The Thin Lens Equation relates object distance, image distance, and focal length for a lens. The calculator works for three possible scenarios: f > 0 and the propagation distance. This calculation is crucial for … Calculate the properties of a thin lens using our Thin Lens Calculator. Easily calculate the focal length of a lens using our Lens Focal Length Calculator. To calculate the focal length of the concave lens in the experiment, we use the following formula: The formula for focal length: f = uv u−v u v u − v. micro pigs for sale com to help keep the site going Q. A convex lens of focal length 40 c m, a concave lens of focal length 40 c m and a concave lens of focal length 15 c m are placed in contact. After you see those 2 videos (by khan academy) I am sure you would understand, But the main reason (spoiler to those videos) to the difference is that. Image Formation for Convex Mirrors. Discover the magic of optics with the Thin Lens Equation Calculator! Calculate focal lengths, image distances, and more effortlessly. Aug 6, 2022 · Our thins lens equation calculator can obtain the image distance of any object after being refracted by a lens of known focal length. How do I determine if a lens is convex or concave? A convex lens has a positive focal length, while a concave lens has a negative focal length. The Thin Lens Equation relates object distance, image distance, and focal length for a lens. The net effect of the refraction of light at these two boundaries is that the light ray has changed directions. It spreads out light rays that pass through it, making objects appear smaller. They offer incredible image quality, swappable lenses, and prosumer fe. The power of a lens can be defined as the ability of a lens to bend the light rays passing through the lens. Enter the two knowns of i, o, and f and press the button. To use this online calculator for Focal Length of Concave Lens given Image and Object Distance, enter Object Distance (u) & Image Distance (v) and hit the calculate button. Simulation of image formation in concave and convex lenses. It demonstrates the inverse relationship. These two types of lenses - a double convex and a double concave lens will be the only types of lenses that will be discussed in this unit of The Physics Classroom Tutorial. Follow a light beam through a concave lens and see what happens! Learn about optics with our interactive concave lens simulation. Follow a light beam through a concave lens and see what happens! Learn about optics with our interactive concave lens simulation.
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Calculate your patient's refraction. The calculator will compute the image distance (d_i), which represents the distance from the lens or mirror to the point where the image is formed. If M is negative, the image is inverted. When a ray parallel to the principal axis hits the lens, it refracts outward as if coming from the focal point. It uses similar triangles and algebraic manipulation to arrive at the formula \ [1/f = 1/d_0 + 1/d_i\], a key concept in optics for premed students. Created by Sal Khan. Light Reflection and Refraction Class 10 MCQ With Answers Pdf Question 1. The principal planes are two hypothetical planes in a lens system at which all the refraction can be considered to happen. Ray Diagrams for Lenses. This calculation is crucial for understanding how optical systems magnify or reduce images, whether in cameras, telescopes, microscopes, or eyeglasses. Since object is always in front of the lens, object distance is always negative. How far is the object placed from the lens ? Draw the ray-diagram. The distance from the lens to the principal focus is called the focal length close focal length The distance between the centre of the lens and the focal point Concave lenses A concave lens is. If the absolute value of M is greater than 1, the image is magnified. It simplifies the calculation of focal points and image distances, making it indispensable for students and professionals in optics. Ray diagrams can be used to determine the image location, size, orientation and type of image formed of objects when placed at a given location in front of a concave mirror. In the equations above R is the radius of curvature, W is the beam radius, i is the square root of negative 1 and &lambda is the wavelength. This calculator gives you the laser spot size and laser beam waist values based on the beam diameter at lens, wavelength, and other parameters you input. Graph functions, plot points, visualize algebraic equations, add sliders, animate graphs, and more. Diverging: Biconcave, planoconcave, and negative meniscus lenses diverge light. Repeat the experiment for different values of u (up to 2. Various types of optical systems (e microscope objectives and curved laser mirrors) can focus or defocus light, and the focal length is used for quantifying such effects. Convex lenses are used for focusing light rays to make items appear larger and clearer, such as with magnifying. ts shemale escorts Sometimes you just need a little extra help doing the math. This calculation is crucial for understanding how optical systems magnify or reduce images, whether in cameras, telescopes, microscopes, or eyeglasses. Is It a good idea to refinance your mortgage? Use our mortgage refinance calculator to determine how much you could save today. Focal power of a plano-concave lens of refractive index 1 Spherical Aberration Correction. Calculate the power of the lens. The thin lens equation gives a relationship between image distance d_i di and object distance d_o do with the focal length f f as below. Tools & Resources. Convex and Concave Lenses | Desmos Explore math with our beautiful, free online graphing calculator. Understanding the principles and calculations involved in determining the effective focal length of a lens combination is essential for various applications, including photography, microscopy, and optical instrument design. Free Functions Concavity Calculator - find function concavity intervlas step-by-step Use the mirror equation calculator to analyze the properties of concave, convex, and plane mirrors. Wolfram|Alpha brings expert-level knowledge and capabilities to the broadest possible range of people—spanning all professions and education levels. The focal length of a lens is dependent upon lens curvature radius and the refractive index. Determine the focal length, object distance, image distance, and magnification for converging and diverging … About The video provides a detailed walkthrough of deriving the lens formula, which relates the object distance, image distance, and focal length in a … Calculators. The combination works as a converging lens of focal length 100 cm. Capturing the essence of our furry friends is no easy task. wellbutrin withdrawal experiences By utilizing a concave lens calculator, users can: Quickly and accurately calculate focal length and image distances for concave lenses. Click here to donate to oPhysics. In order to apply a cultural lens on a situation, soft skills like empathy and underst. The passage of light through simple concave and convex lenses is governed by the principles of refraction, and can be understood with the aid of a few simple rules about the geometry involved in tracing light rays through the lens. Within a few paragraphs, you will learn: What the thin lens equation is; How to calculate image distance using the image distance equation; and; The magnification equation for lenses. Draw a ray diagram to show how an image is formed by a concave lens. This part can be used to create a wide variety of lens forms, including any combination of concave and convex lens surfaces. Like a convex lens, there is a principal focus on both. A lens is a transparent material (either curved or flat surface) based on the principles of refraction. Bi-concave lens, precision grade. Click here to donate to oPhysics. The Lens Maker's Calculator uses the Lens Maker Equation 1 to calculate the focal length of a thin lens in air (or some other medium). A ray from the top of the object proceeding parallel to the centerline perpendicular to the lens. rare 50p coin list Two sliders let you produce shapes ranging from a thick bi-convex lens to a thin bi-concave lens. Let's explore the magnification formula (M= v/u) for lenses and see how to find the image height and its nature (whether it's real or virtual). Examples are given for converging and diverging lenses and for the cases where the object is inside and outside the principal focal length. The Thin Lens Equation Calculator aid in determining critical parameters such as the focal length, object distance, and image distance. com to help keep the site going Q. Move the tip of the "Object" arrow to move the object. Within a few paragraphs, you will learn: What the thin lens equation is; How to calculate image distance using the image distance equation; and; The magnification equation for lenses. Understand how varying lens parameters affect optical properties such as magnification and image clarity. The video provides a detailed walkthrough of deriving the lens formula, which relates the object distance, image distance, and focal length in a convex lens. Within a few paragraphs, you will learn: What the thin lens equation is; How to calculate image distance using the image distance equation; and; The magnification equation for lenses. If the absolute value of M is greater than 1, the image is magnified. - Drag to move the object and the focus - Shift + drag to move the sheet - Shift + roll to zoom. The Thin Lens Equation relates object distance, image distance, and focal length for a lens.
The distance from the lens to the principal focus is called the focal length close focal length The distance between the centre of the lens and the focal point Concave lenses A concave lens is. The principal focus of a concave lens is the point where rays hitting the lens parallel to the axis appear to have come from. Draw a diagram to show the formation of image and. Lenses can curve in one of two directions, either inward or outward, and thus lenses are broadly categorized into two types: the bi-concave lens (or simply concave lens) and the bi. cz shadow 2 fiber optic front sight replacement It demonstrates that the ratio of the distance from the object to the lens, to the distance from the image to the lens, is the same as the ratio of the height of the object to the height of the image The behavior of concave lenses can be described by the lens equation, which relates the object distance (do), the image distance (di), and the focal length (f) of the lens: 1/f = 1/do + 1/di. When using the lens equation with a concave lens, however, the focal length must be assigned a negative value. Fill in the input fields and then press the Calculate button in order to compute the approximate center and edge thickness (through the 180°) produced by a spectacle lens. com to help keep the site going Q. This calculator shows a ray diagram when the image is real. This equation relates the vergence of a thin lens with the radius of curvature of its two faces and the refractive indice of the lens material. Understand how varying lens parameters affect optical properties such as magnification and image clarity. The distance between the center of the concave lens and its principal focus is called its focal length. katiana noodles The video provides a detailed walkthrough of deriving the lens formula, which relates the object distance, image distance, and focal length in a convex lens. A concave lens is a lens that possesses at least one surface that curves inwards. converging lens (f > 0 f > 0) with close object (s < f s < f) - This time the thin lens equation results in an image distance that is negative, because 1 s > 1 f 1 s > 1 f. The most abundant type of lenses is the spherical shape. mannys beach club airbnb This calculator shows a ray diagram when the image is real. The focal length calculator allows you to compute magnification, angle of view as well as the focal length needed for a picture of a distant object. Hence, the focal length of the lens is 25 cm. Move the tip of the "Object" arrow to move the object. Enter the two knowns of i, o, and f and press the button. Learn how to calculate the height of an image for a concave mirror, and see examples that walk through sample problems step-by-step for you to improve your physics knowledge and skills. Step 3: Finding the power. Move the point named " Focus' " to change the focal length.
The most notable benefit of aspheric lenses is their ability to correct for spherical aberration, an optical effect which causes incident light rays to focus at different points when forming an image, creating a blur. Move the point named " Focus' " to the right side of the lens to change to a concave lens. This video explains the thin lens formula and its components: focal length, object distance, and image distance. Master the technique of calculating the focal length of a lens with our easy-to-follow guide, essential for choosing the right lens for your photography needs. The video provides a detailed walkthrough of deriving the lens formula, which relates the object distance, image distance, and focal length in a convex lens. We also learned about three simple rules of refraction for double concave lenses:. They offer incredible image quality, swappable lenses, and prosumer fe. Interaction with Incident Light Rays. To calculate Object Distance in Concave Lens, you need Image Distance (v) & Focal Length of Concave Lens (F concave lens). Power of the lens = 1 − 2 = − 0 Hence the power of the lens is -0 Diverging lenses do not form real images. Understand how varying lens parameters affect optical properties such as magnification and image clarity. why is the mirror formula and the lens formula totally different and just opposite of each other's formula and even the magnification formula. You can use this tool find position of the final image formed by the combination of the two lenses, and magnification of the final image formed by the combination of the two lenses. Choose from N-BK7 glass, UV fused silica, or CaF 2, all of which are available uncoated. It can form both real and virtual images. We can differentiate between them by observing the focal length. They can be used in beam expanders and projection systems With a concave lens, the image will always be diminished, the right way up and virtual. Aug 6, 2022 · Our thins lens equation calculator can obtain the image distance of any object after being refracted by a lens of known focal length. A concave lens produces an image 20cm from the lens of an object placed 30cm from the lens. weight loss coach jobs This calculation is crucial for understanding how optical systems magnify or reduce images, whether in cameras, telescopes, microscopes, or eyeglasses. With this tool you can calculate the required focal length to take a picture of an object at a given distance in order to generate an image fitting on your sensor size. Cylindrical Lenses. This calculation is crucial for understanding how optical systems magnify or reduce images, whether in cameras, telescopes, microscopes, or eyeglasses. and the corresponding focal length f = cm. Easily calculate the focal length of a lens using our Lens Focal Length Calculator. How do I determine if a lens is convex or concave? A convex lens has a positive focal length, while a concave lens has a negative focal length. Determine the focal length, object distance, image distance, and magnification for converging and diverging … About The video provides a detailed walkthrough of deriving the lens formula, which relates the object distance, image distance, and focal length in a … Calculators. The passage of light through simple concave and convex lenses is governed by the principles of refraction, and can be understood with the aid of a few simple rules about the geometry involved in tracing light rays through the lens. Enter the two knowns of i, o, and f and press the button. Actual results will differ! Our sales team will be happy to assist you! Focal Length Calculator. Build your lens and watch the incident rays converge or diverge. This calculation is crucial for understanding how optical systems magnify or reduce images, whether in cameras, telescopes, microscopes, or eyeglasses. The figure has arrows leading the user to the different variables used in the Axicon's. 33 has a concave surface of radius 60cm and convex with radius r= +30cm. Overview of diverging lenses: A diverging lens, also known as a negative or concave lens, is characterized by being thicker at its edges than at its center. A concave lens produces an image 20cm from the lens of an object placed 30cm from the lens. This is an online calculator to find the focal length of a lens. To calculate Object Distance in Concave Lens, you need Image Distance (v) & Focal Length of Concave Lens (F concave lens). This physics video tutorial provides the ray diagrams for a concave and convex mirror. A concave lens has a focal length of 20 cm. This is an online calculator to find the focal length of a lens. northwestern post bacc pre med reddit Click here to donate to oPhysics. The size of the image is highly diminished and point size. Simulation of image formation in concave and convex mirrors. Just enter the object size, image size, and object distance to get the magnification, angle of view, and focal length value. 24. When a parallel beam after refraction through the lens is incident on a concave lens, if appears to diverge from the focus of the lens. They have a negative focal length and are used to diverge incoming light, or to increase focal length in an existing optical system. The distance from the lens to the principal focus is called the focal length close focal length The distance between the centre of the lens and the focal point Concave lenses A concave lens is. With our tool, you need to enter the respective value for Image Distance & Focal Length of Concave Lens and hit the calculate button. Understanding optical lens geometries helps anyone, from novice to expert, choose the best optical lens in any optical design. The next type of lens which is called the toric lens has 2 distinct radii of curvature. Explore concave & convex mirrors, ray diagrams guidelines and image formation examples. Abstract. The magnification of a lens can be described using the same parameters: M = −S2 S1 = f f − S1 M = − S 2 S 1 = f f − S 1. The minus sign means that the lens is a concave (diverging) lens. 2, in which light can travel from a source to another location. Like a convex lens, there is a principal focus on both. It can be calculated from the lens-maker's formula for thin lenses. v: distance between I' and the optical center of the lens L2. 1 − (-0032. The distance between the center of the concave lens and its principal focus is called its focal length. Convex lenses are used for focusing light rays to make items appear larger and clearer, such as with magnifying.