Dhanush Shivaramaiah
What does object space and image space mean in optics?
What does object space and image space mean in optics?
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hi thereDhanush Shivaramaiah said:
welcome to PF
You have labelled your thread with an "A" tag implying that you have a post graduate level of education
So what research have you done so far on the topic ?
what have you been reading and what didn't you understand ?Dave
Dhanush Shivaramaiah
I'm really sorry, sir. I did not know what the tags meant as I'm new. I just registered today. I'm a 12th grade student.
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Dhanush Shivaramaiah said:
all good, no problems
So have you tried putting your question into google ?
what did you discover ?
there are lots of links and references there for you to have a read through
and then come back with questions on anything specific you didnt understand
Dave
Dhanush Shivaramaiah
Sure, sir. I googled these problems and read extensively. From what I understand optical space is a co-ordinate system like a Cartesian coordinate system. Object space is the space where the rays emerge and image space is the space is space where rays fall or appear to fall.
This is what I understood so far. Please correct me if I'm wrong. I'd be very happy if anyone can provide further information or correct me if I'm wrong.
This is what I understood so far. Please correct me if I'm wrong. I'd be very happy if anyone can provide further information or correct me if I'm wrong.
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Dhanush Shivaramaiah said:
You have the right idea. Object space is the space between the source and the optical system; image space is the space between the optical system and the image.
If I remember my Optics 201 and 202 classes correctly, object and image space don't necessarily correspond to physical spaces and can even be in the same physical space. For example, when you look in your bathroom mirror the object and image space coincide. These spaces can even extend to opposite sides of a lens. The entrance pupil for an optical system (which always occupies object space) may actually fall behind the last lens, in the physical space where the image is formed, while the exit pupil (which always occupies image space) can fall in front of the system in the physical space the object occupies.
As an example, the exit pupil of a cassegrain telescope lies behind the secondary mirror, meaning that the exit pupil is at the front of the telescope, just like the object is. Despite this, the exit pupil is still in image space, not object space.
To get more technically accurate, both image and object spaces are specific types of optical spaces and both extend to infinity in all directions. They are merely mathematical tools to help us analyze and design optical systems. Rays moving from one medium to another (air to lens) undergo a "mathematical transformation" and enter another optical space. This mathematical transformation is just terminology that means that we are performing the same mathematical operations on all of the rays, such as using the laws of refraction or reflection to find their new trajectory.
As an example, the exit pupil of a cassegrain telescope lies behind the secondary mirror, meaning that the exit pupil is at the front of the telescope, just like the object is. Despite this, the exit pupil is still in image space, not object space.
To get more technically accurate, both image and object spaces are specific types of optical spaces and both extend to infinity in all directions. They are merely mathematical tools to help us analyze and design optical systems. Rays moving from one medium to another (air to lens) undergo a "mathematical transformation" and enter another optical space. This mathematical transformation is just terminology that means that we are performing the same mathematical operations on all of the rays, such as using the laws of refraction or reflection to find their new trajectory.