Optic neuropathy is damage to the optic nerve from any cause. Damage and death of these nerve cells, or neurons, leads to characteristic features of optic neuropathy.
The main symptom is loss of vision, with colors appearing subtly washed out in the affected eye. On medical examination, the optic nerve head can be visualised by an ophthalmoscope. A pale disc is characteristic of long-standing optic neuropathy. In many cases, only one eye is affected and patients may not be aware of the loss of color vision until the doctor asks them to cover the healthy eye.
Optic neuropathy is often called optic atrophy, to describe the loss of some or most of the fibers of the optic nerve. In medicine, "atrophy" usually means "shrunken but capable of regrowth", so some argue that "optic atrophy" as a pathological term is somewhat misleading and the term "optic neuropathy" should be used instead.
In short, optic atrophy is the end result of any disease that damages nerve cells anywhere between the retinal ganglion cells and the lateral geniculate body (anterior visual system).
Hello All,
I recently purchased a BW Tek BTC100-2s spectrometer from eBay. It has fairly good specifications, but I have been wondering if there is an inexpensive way to improve its resolution. The spectrometer uses a Czerny-Turner configuration. My plan was to place a slit at the focal length...
Hi! I'm working in a lab this summer doing quantum optics, and my team is working on a Mach-Zehnder interferometer setup. We got it well aligned and interference fringes appeared as expected. However, soon after building it, the fringes began to fade in and out of view without us changing...
So I have a problem understanding the difference between working distance and the object distance of a lens.
For me it is also unclear what the difference between image distance and back focal length.
If I want to enlarge the image by 6. How can I calculate the focal length, object distance...
I have a camera that take pictures of square boxes that are really close to one another. There is a light that is Illuminating the boxes but when I try and isolate a single but in my picture, I am reading higher values then what I should be. If I remove the other boxes and only do one box, I am...
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I have a personal art project and I am stuck, because of very limited knowledge.
I'd like to project an 1-2 meter white line from 1-3 meter distance. The projected line should be as thin as possible (3-10mm) and as powerful as possible. I created a DIY projector, but my problem is that, the...
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suppose we are given a biconvex lens with focal length of 4 cm. Further, an arrow of height 1 cm is placed in front of the lens in a distance of 8 cm (i.e. twice the focal length). Lastly, a mirror is placed on the other side of the lens at a distance of 4 cm and such that it performs an...
Homework Statement
A transparent film( n = 1.45) is placed on a glass surface( n = 1.14) and is illuminated by light ( incidence angle α = 60°. What is the minimum thickness d1 of film such that reflection of light with λ is minimized, while if the thickness is d2 then with the same λ the...
According to me this topic must be raised and discussed how fermat did it without calculus.What problems he faced since calculus was developed afterwards by Newton leibniz.
http://aapt.scitation.org/doi/10.1119/1.1514235
Moderator's edit: File substituted by link due to potential copyright...
Homework Statement
Draw the ray diagram of the case of a diverging lens where both object and image are virtual, that is ##f<0## , ##p<0## with ##p<f## Homework EquationsThe Attempt at a Solution
I did not find this particular case of ray diagram in any textbook so I would like to know where...
Homework Statement
Consider a glass plate of refraction index n and thickness ## \Delta x ## placed between a point monochromatic source S and an observer O, as in picture.
(a) Prove that, if absorption from the plate is neglegible, then the effect on the wave received by O is the add of a...
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I have one question or maybe some questions about creation an optical system. I have a drawing of the system (see below) where are placed 2 right angle prisms. The aim of this is to reflect image from "A" to "B". I suppose that I will need to add some lenses to do it right without...
Homework Statement .[/B]
I am attempting to determine the group refractive index of a laser cavity at it's resonance frequency.
Homework Equations .[/B]
\begin{align*}
\frac{2\omega n L}{c} &= 2m\pi
\end{align*}
\begin{align*}
n_g &= n + \omega \frac{dn}{d\omega}
\end{align*}
3. The attempt...
Homework Statement
A pentaprism is a five-sided reflecting prism used to deviate a beam of light by 90◦ without inverting an image. Pentaprisms are used in the viewfinders of SLR cameras.
(a) What prism angle β is required for a normal-incidence beam from the left to exit the bottom surface at...
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This question is from 1990 Turkey National Physics Olympics. I tried my best to translate it clearly.
1. Homework Statement
https://s23.postimg.org/cotn29afv/Hollow+Spherical+Glass.jpg
The sphere of radius 2R has an empty sphere inside with radius R. In order for the image of an object...
Homework Statement
An observer looks at an object of height 2 cm through a plane-convex lens of radius 20 cm and refraction index 1.5. There's a concave mirror of radius 30 cm 40 cm behind it, and the object is at the same distance of both the lens and the mirror. Find the images formed by the...
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I have an optic problem
I want to calculate absorbtion index
I know transmittance by 90% ;refraction index to material 1.586 ; thickness 2 mm ; power of source 21 lm