Lens Definition and 787 Threads

I am trying to create a beam expander. I purchased 3 double convex and 3 double concave lens (200mm, 300mm and 500mm). But for the diverging concave lens I need a negative -500mm lens. What exactly is a negative concave lens? I am unable to find anything on amazon or any other site that has a...

Good day all, I am searching for some advice on how I could successfully take photos of a surface that is 5mm away from a CMOS camera sensor. My ideas so far are; 1.) Find a lens with sub millimeter focal length (0.2mm by my calculations) 2.) Utilize mirrors to increase object distance 3.) Pin...

I used a green laser pointer (λ = 532nm). I aimed it at a divergent lens that has a focus of -50cm. The distance from the laser does not play a big role. As a result, a very clear interference pattern with a series of concentric circles appeared on the screen. I did not find a suitable...

Question 1. i Suggest a reason why any uncertainty in the values of u can be neglected. I am really rather unsure how to answer this question but I have produced my opinion nonetheless. One could assume that the uncertainty in object distance u, i.e., the distance from the lens to the light...

I know how to solve the problem but the only thing that's bothering me is what is A? According to me A is should be 2F ie 2 times the focal length distance. I thought of it like this: 1. First there will be an image formed due to the lens. 2. The image will be formed below the lens but the...

Hello Everyone, I have been working on a lens design that requires a concentric meniscus lens. Initially I was under the impression that r1 should equal r2 for the light to exit at infinity when entering at infinity. However my ray diagram shows different, it shows the light is being bent...

Hello All, I am in need of an optics expert on imaging, and in particular a fresnel lens is being used as for an imaging device. From my understanding a condenser lens can be considered equivalent to a plano-convex lens. Setup: A condenser fresnel lens is used, for which both the fresnel and...

When you put a 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...

If i put a rotating stick behind lens of several types, so the stick center is behind the lens center, will the stick edges always appear to move at the same rate as areas closer to the stick center?

Hello, I wanted to confirm a suspicion with how the Aimpoint optics work, but to do that I need to do some ray diagrams. I only ever did them with simple convex, concave, and spherical systems while at college. From what I already know of how reflex sights work, the LED is placed at the focal...

The picture below shows a so-called chromatic doublet, which is designed to minimize chromatic aberration, ie the wavelength dependence of the refractive index of the glass. The first lens has a flat first surface and a concave second surface with radius of curvature R and index of refraction n1...

Hello, I am trying to get a better understanding of optical lens's and came across a question I have not found an answer to. Say you have a lens made of either Polycarbonate or Trivex, and it is a spherical lens. A coating is applied to the side with the smaller radius to reflect certain light...

I have an plano-convex lens with focal length 75 mm. The object is 325mm from the lens. a) Where is the location of the image after the lens? b) Where is the location of the image if an beamsplitter is placed after the lens? My solution, questions: a) a = 325 mm b = ? mm f = 75 mmm...

Since the two lenses are plano-concave and plano-convex, the lens maker equation can be simplified into containing only 1 R for each of the lens. Substituting the values for the red light, I got: 1/f1=0.51/R1 and 1/f2 = 0.64/R2. Adding these two equations and equating them to 1/(500*10-3)...

By drawing arrows, I can find out the following: Since they are in different phases, I get: ##2nt=m \lambda## for dark fringes. In this case, they want me to find the radius of curvature. I'm not sure what to really proceed on here. What I figured out so far is that I will be able to find the...

Hi all, So far all the problems I dealt with is dealing with double slits when working with dark and bright fringes. In this case, what should I do in regards with a lens? Also, what does the question mean when it asks for the minimum distance that the lens can resolve on the screen? Does it...

I am trying to come up with a design for a device that can generate very high and very brief waves of pressure directed at a 1 mm diameter target (shown as "E" in "Diagram.PNG") housed in a steel support structure "D". The idea is to accelerate hammer "A" towards anvil "B" in a vacuum tube. The...

A thin lens has an upper radius of curvature 𝑅1 and a lower radius of curvature 𝑅2. When the lens is completely surrounded by air, it has a focal distance 𝑓. The lens is then placed in the interface between air and water inside a vessel (see figure). Calculate the refractive index for the glass...

Homework Statement:: Finding the distance between the back surface of the first lens and the front surface of the back lens. Homework Equations:: 1/f = 1/s_o + 1/s_i I have two positive thin lenses that are separated by a distance of 5 cm. The focal lengths of the lenses are F_1 = 10 cm and...

Suppose one light up with a laser on a grid with grid constant g. The grating is followed by a focusing lens with a focal length of f. In the focus (or immediately in front of it) the maxima have a distance d. How large was the distance of the maxima immediately after the grating? scheme: Laser...

Homework Statement: Lens questions. Homework Equations: idk Hello, so I was wanting to use a laser beam and purchase a few lens' online for a project and wanted to get something similar to the image below, where i would end with a horizontal light ray i was wondering if anyone knows the...

I am aware that the object would be to the left of the lens and the image would be to the right, but I don't understand what it is mean by " A converging lens of focal length f = 8.96 cm forms a sharp image for two positions of the lens." I don't understand where the two positions would be and...

Homework Statement: what is the mathematical explanation for fresnel lenses Homework Equations: No equations were provided I'm going to post a link to one article I found that I think has the answer, but I couldn't understand because of my lack of knowledge in physics and math...

Summary: Hi, I'm doing an assessment for Physics on Optics topics, but I can't really explain how the CV affect the RV CV : Focal length of convex lens RV : Temperature of water after 20 minutes under the sun How I should explain for the temperature difference? 🤔 Please help, Thanks.

A quick search turned up Simaciu, Ion. (1997). Chromatic aberration of gravitational lens. 10.13140/2.1.1133.6003. The math is beyond me so I first made a basic assumption that chromatic aberration of gravitational lenses worked somewhat analogous to a prism in that red is bent less than other...

I don't really know how to relate the effective and back focal lengths for magnification purposes. Literature review suggests that a lens of 1mm diameter can have a magnification of 350x-400x, but I don't really know the calculations behind it. Please advise.

Summary: Will an external surface reflect light into a more focused beam without using a traditional lens? Hey guys. Just trying to focus the light coming from a 1watt LED light source. It's native beam angle is 130 degrees. I'm hoping to focus it to around 30 degrees. We are creating an...

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Leitz Summicron 50 is one of the extremelly well corrected lens in the world. Legend says about this lenses internal elements and their spherical aberrations was responsible of lot of beatiful effects on image. For highly corrected lens image , does high internal aberration really effects the...

I'm a physics student, and working on a class project that requires coming up with a method to control the exit angle (diffraction angle) of a monochromatic light source. For example, taking a laser (monochromatic, coherent light source), spreading the beam, and directing the light at a piece...

I tried -M=pq = f/(f-p) = f/f - f/p = 1-(f/p) => M+1= -f/p => -Mp-p=f But since it’s the y intercept, p will equal zero and so the focal length will be 0?

My teacher taught me a formula for magnification in case of Compound Microscope, Magnification=(Angle Made By Object On Aided Eye)/(Angle Made by Object on Un-aided Eye) Can I use this formula for calculating magnification of Astronomical Telescope? Thanks!

Is it possible to get a real image of virtual objects, If so please explain with examples and some real life situations? Look at my assertion "rays will not pass through virtual objects so how it can form real image", is this possible, please help.

Homework Statement A hyperopic eye has a near point of 1.10 m. Calculate the focal length of the spectacle lens required to correct the hyperopia (assume that the near point of the normal eye is 25.0 cm.) Homework Equations 1/f=1/p+1/q The Attempt at a Solution I just used .25 m as p and...

Hello, i just wanted to ask if you can explain to me what thermal lens effect is? I am supposed to answer why laser beam passing through ink or soy sauce creates this effect and i can't find any information on what actually this thermal lens is. I know of course that it is a lens, but why does...

I need to design a mini projector as a part of a project I am working on. The body of the projector is approximately 7 inch tall and 5 inch wide. I don't know what kind of a lens I need to ensure the projection is sharp and crisp (it is only black and white writing). I know I would need a zoom...

Homework Statement An arrow of 2cm length stands about 6cm away from a convex lens (f = 2cm). How long is the image of the arrow? Homework Equations - The Attempt at a Solution Whenever I get homework regarding optics and particularly the lens formula, I never really know where to start. I...

Homework Statement A thin convex lens of focal length 20 cm is split into two parts along the principal axis, now there is a 2mm gap between the top and bottom parts, an object O is placed at 10 cm from the lens, the distance between the two virtual images will be? Homework Equations 1/v - 1/u...

Hello My question has two parts: 1) Why is plano convex lens used in slide projector? Why can't we use simple convex lens in it? 2) Why are two plano convex lenses used in slide projector? Why can't we use only one?Thanks!

Hi I want to make a infrared nonimaging concentrator, but since crystals needed for lenses are difficult to work with for an amateur, want to use liquids. I am interested in the 1-12 micron spectrum; what liquids could i use?

Homework Statement An object is 25.0 cm to the left of a lens with a focal length of + 15 .0 cm. A second lens of focal length +15.0 cm is 30.0 cm to the right of the first lens. Find the location of the final image and draw it out. Homework Equations 1/f = 1/di + 1/do The Attempt at a...

Hi I'm reading through a Quantum Mechanics textbook called Quantum Mechanics by Book by Alastair I. M. Rae and in the opening chapter it talks about the Heisenberg uncertainty principle and talks about how a measurement of position of a particle causes an uncertainty from the momentum due to the...

Homework Statement Two slits (of width ##a=39 \mu m##) are lighted up with a monocromatic wave of ##\lambda=632,8 nm##. The distance between slits and the screen id ##D=4 m##. The distance between the slits id ##d=195 \mu m##. In front of the slits there are a convergent lens with focal length...

Hey everyone, I've been researching for some time now, and I can' find anything about how the actual lens blanks for prescription eyeglass lenses are made, I've looked on websites like this: http://glassescrafter.com/information/how-prescription-glasses-are-made.html but it only explains how the...

Homework Statement Homework EquationsThe Attempt at a Solution The photoelectric current is directly proportional to the intensity of the light falling on it . It will not depend on the focal length of the lens . When the lens of half the diameter is used , intensity is halved . This...

Homework Statement It is desired to magnify reading material by a factor of 3.5× when a book is placed 9.5 cm behind a lens. What is the power of the lens in diopters? Homework Equations 1/f = 1/di + 1/do M = -di/do P=1/f The Attempt at a Solution I set equal the magnification to -di/do and...

Homework Statement This isn't really a homework, but I am trying to figure out how this would work. I have an plano-convex lens with an focal length of 500 mm. I have an laser source that I like to focus on, to the infinity. I.e. I like to see the laser lobe. Case: What happens to image of...

Hello, I have a small project in which I try to use a Time of Flight camera to detect movement in the Field of View. Now the current Field of View is really narrow (about 25° diagonal FoV), which is we I will have to simulate a bigger one. My professor did try to explain to me what changes...

We have the mirror equation (1/v) +(1/u)=(1/f) and the lens equation (1/v) - (1/u)=(1/f) Where u =object distance from the mirror/lens v =image distance from the mirror/lens f =focal length of the mirror /lens My doubt is, when we are doing some problems in optics using these...

I read maxwell says electric field polarizes the dielectrics. Does it mean above effect used at photographic camera lens design to make that lens sometimes works like polarizer filter ? Mustafa Umut Sarac Istanbul