Lenses are used to make glasses in order to correct vision issues. Do some research about...

Lenses are used to make glasses in order to correct vision issues. Do some research about vision deficiencies, what causes them and how we can utilize different types of lenses to fix them

Expert Solution

There are mainly three types of vision disorders:

Nearsightedness/Myopia : Myopia is often called nearsightedness, because people who have it can only see nearby objects in sharp focus.

Cause: It is caused by too much curvature of the cornea relative to the length of the eyeball. This causes the light rays in the eye to be focused in front of the retina instead of on it.

Correction lens : concave lens

Farsightedness/ Hypermetropia :
Hypermeteopia, or farsightedness, is just the opposite – people with it can see clearly far away, but not close up.

Cause :It is caused by insufficient curvature of the cornea relative to the length of the eyeball. This puts the focal point of the light rays behind the retina instead of on it.

Correction lens : convex lens

Presbyopia :

Presbyopia is an age-related condition that occurs as the lens loses its ability to change shape. This reduces the eye’s ability to adjust for different distances, especially close up, so that the weakly bundled light rays are not focused at the retina.

Cause : Age factor.

Correction lens : bifocal lens (both concave and convex lens)

Astigmatism :

In astigmatism, the cornea is misshapen and does not properly focus the light entering the eye. Instead of hitting the retina in a focused point, the light is spread over two or more points. The result is a blurry or stretched image.

Correction lens : toric lenses, they can bend light more in one direction than the other.

genius_generous answered 2 years ago

a) When glasses (or contact lenses) are usedto correct nearsightedness, where should the corrective lens forman image...

a) When glasses (or contact lenses) are usedto correct nearsightedness, where should the corrective lens forman image of an object located at infinity in order for the eye toform a clear image of that object? The lensshould form the image at the near point. The lensshould form the image at the far point. The lensshould form the image at a point closer to the eye than the nearpoint. The lensshould form the image at a point farther from the eye...

The Focus on Vision Foundation says it can product its Focusspec glasses for about $4 a...

The Focus on Vision Foundation says it can product its Focusspec glasses for about $4 a pair. When originally announced, the Dutch firm planned to distribute about 30,000 pairs in early 2010 in Afghanistan, Ghana, and Tanzania. The advantage is that these are self-adjusting glasses, designed so that untrained wearers could set the right focus themselves. This attribute is quite important given the lack of access to vision care professionals throughout parts of Africa and Asia. In order to determine...

Question 1: A near-sighted person might correct his vision by wearing diverging lenses with focal length...

Question 1: A near-sighted person might correct his vision by wearing diverging lenses with focal length f = -50cm . When wearing his glasses, he looks not at actual objects but at the virtual images of those objects formed by his glasses. Suppose he looks at a 12cm -long pencil held vertically 2.0m from his glasses. Use ray tracing to determine the location of the image. Answer is in meters. Question 2: A 1.0-cm-tall object is 60 cm in front...

Bifocal glasses are used to correct both nearsightedness and farsightedness at the same time. (Figure 1)...

Bifocal glasses are used to correct both nearsightedness and farsightedness at the same time. (Figure 1) Part A: If the near points in the right and left eyes are 38.0 cm and 46.0 cm , respectively, and the far point is 210 cm for both eyes, what are the powers of the lens prescribed for the right eye? (Assume that the glasses are worn 3.00 cm from the eyes.) Part B: What are the powers of the lens prescribed for...

Do some research on diversity in organizations. Some issues you might want to examine include finding...

Do some research on diversity in organizations. Some issues you might want to examine include finding specific situations where organizations have benefited through enhanced diversity (e.g. improved product, better customer service) or situations where an organization has been hurt through their lack of diversity. Is it always the case that diversity leads to improved performance (be civil, professional and data driven in assessing this!)? Write a discussion post with the following - a brief summary of what you learned about...

Try to make it as simple as you can. You need to do some research on...

Try to make it as simple as you can. You need to do some research on different types of cryptography libraries in Python. Find out how can we use cryptography libraries in Python. Write down the steps to install the cryptography library in Python. Write a small program to encrypt and decrypt a message using the Python library.

1. How do the three objective lenses on the microscope you used differ and what are...

1. How do the three objective lenses on the microscope you used differ and what are the advantages and disadvantages of each? 2. How variable were the lengths of Paramecium caudatum cells relative to the lengths and widths of the cells you observed in Elodea leaves? 3. What size range did the single eukaryotic cells you examined span? 4. What subcellular features did you recognize and identify in all of the organisms you examined 5. Did you examine any prokaryotes...

In the past, researchers in psychology used some "ethically questionable" research techniques. Do you believe that...

In the past, researchers in psychology used some "ethically questionable" research techniques. Do you believe that some of these techniques were useful despite their ethical shortcomings? Explain. How did these “ethically questionable” techniques lend to the creation of the code of ethics?

Do some research and tell the class why horizontal and vertical analysis methods are used. What...

Do some research and tell the class why horizontal and vertical analysis methods are used. What can we learn from these statements? How can the results be compared to other corporations and why are ratios better than using dollars?

Which of the following is (are) correct about mixed-methods research? i. A research instrument can be...

Which of the following is (are) correct about mixed-methods research? i. A research instrument can be employed to produce both objective measures and subjective narratives. ii. When there are discrepancies between the quantitative and qualitative sets of findings, it means there is no feasible explanation for the social phenomenon under investigation. iii. Qualitative data can be used to inform the formulation of hypotheses that can be tested via quantitative methods. iv. Mixed-methods research produces data of a higher level of...

Question