All Questions
20
questions
0
votes
1
answer
61
views
What happens when screen is not placed where Image is focused but elsewhere?
When we try to form a real image on a screen by a convex lens, we place the screen at a distance where the image is focused. But if we try to place the screen at a distance less than the distance ...
- 187
3
votes
2
answers
365
views
Ideal surface for a perfect lens
in this physics lecture, on slide 15-16, it is found that the ideal surface for a perfect lens (which maps a plane wavefront into a perfect spherical wavefront, i.e. which makes focus all input ...
- 1,319
0
votes
1
answer
65
views
Why do some anti-reflective (or anti-glare) lenses use layers of materials with alternately very high and very low refractive indices?
Some specials lenses like this (or coatings on them) try to minimize the refractive index, or the change thereof, or at least make the change very gradual.
But others apparently do the exact opposite, ...
- 4,509
1
vote
1
answer
321
views
Regarding measurements on traveling microscope
In a experiment with traveling microscope to determine thickness of a glass slab , what is the physical significance of the readings that we get from the vertical scale ?, Means What are two points ...
1
vote
0
answers
42
views
Extraordinary wave [closed]
In anisotropic media, for extraordinary wave, I don't understand how can the power flow not be in the same direction as the propagation. I can't find a physical intuition for it.
- 43
1
vote
1
answer
20
views
Is it possible to optimally transmit solar radiation by a system of multiple optical fibers?
As we all know, if an optical fiber is designed with the right material and properly bent, light can be transmitted along the fiber with very little attenuation.
Figure 1 shows the interaction of ...
1
vote
0
answers
29
views
Doubt regarding simple microscopes [duplicate]
As my textbook stated we use a convex lens of small focal length $f$ to keep an object at a distance such that the image is produced at a distance $D$ (our least distant clear vision point is around $...
- 182
1
vote
1
answer
39
views
Why are very thick soap bubbles colorless?
Is it simply because the wavelength where constructive interference occurs gets to be too long?
- 23
0
votes
0
answers
27
views
Is there an optic which reflects RCP beam and transmits LCP beam, or vice versa?
I'm currently looking for an optic which reflects the right circular polarized (RCP) beam and transmits the left circular polarized (LCP) beam, or vice versa. I prefer the incident angle of 0 deg but ...
2
votes
1
answer
379
views
Focal plane of ideal thin lenses and spherical mirrors
Recently I was studying about optical instruments and in my book I came across a point which stated that
When non axial parallel rays are incident on an ideal spherical mirror at a small angle or a ...
- 1,536
1
vote
2
answers
759
views
Magnifying power of a microscope for a farsighted person
I was doing some problems on optical instruments and in one of the questions it was asked that if a simple microscope(magnifying glass) has a magnifying power 5X for a normal relaxed eye.. what will ...
- 33
1
vote
1
answer
473
views
Why does the definition of angular magnification relative to the substended angle of least distence that the eye can see
The angular magnification defined as,
angle subtended by image of object /angle subtended by object when 25
cm from the naked eye
Consider this.
An object is placing 50cm in front of a convex ...
- 222
0
votes
1
answer
152
views
How can I make a Telescope with the lenses I have
List of lenses I have
Convex - 200mm F.L - 50mm Dia
Convex - 50mm F.L - 50mm Dia
Convex - 40mm F.L - 40mm Dia
Convex - 45mm F.L - 25mm Dia
Concave - 200mm F.L - 50mm Di
I tried to make a ...
- 101
1
vote
1
answer
445
views
The numerical aperture of optic fibre and angle of incidence
First
My college book contains the following passage:
the angle of incidence (relative to the fibre axis ) can't be too large else the ray would be refracting on the core\cladding boundary and ...
- 161
1
vote
1
answer
505
views
What determines how much partial reflection occurs at a boundary between two media?
Some thoughts I had about this are:
does it depends on the two media? Surely it must do. If so, what properties of the media dictate the extent of partial reflection?
this point is highly dependent ...
- 3,997