Optical systems are studied under two assumptions
object point does not lie far away from the axis of the optical system.
rays taking part in image formation make a small angle with the axis of the optical system.
The domain of optics where above two assumptions are valid is called as Paraxial optics. Paraxial systems are highly idealized and in reality do not perfectly represent the situation. The consequential errors in image reconstruction are known as aberrations.
The paraxial assumption can be represented by truncating at the first term of the polynomial expansion of the sin function by the Maclaurin series. More…
Stationary state and squirrels !
Okay so the squirrel isn’t moving around so much, giving a fuzzy image. We can call the instant during which the squirrel wasn’t moving akin to a “gross” stationary state.
But why is the railing of window fuzzy? It isn’t moving !
Due to diffraction enough light is coming from the other side of the iron bar, to enable us to see whats there. That quadrangle is diffracting the light. But why its fuzzy?
Diffraction is by its own very nature even though purely classical in many sense, fuzzy towards energy if time window is small. [due to energy vs time uncertainty]
That is, full energy cycle isn’t available, because a small time window is chosen. If you time-lapse the photograph, diffraction will become quite insignificant. Although it might still be there depending on details. More…
Caption (#mdashf): I am the only person who has taken the picture of all of humanity keeping myself impossible to be pictured by anyone.
The Viral-nova caption is kind of not clear;”This photo was taken by astronaut Michael Collins, when he took this photo he was the only human, alive or dead, that wasn’t in the frame of this picture. He traveled with Buzz Aldrin and Neil Armstrong and orbited the moon whilst they were landing to study the surface of the moon from farther out.”
Caption: (#mdashf) Dear Galaxies, we just clicked your 10 billion year old picture.
100s of galaxies seen through the Hubble Deep Field (HDF), as they were 10 billion years ago.
Above our moon, are seen the planet Jupiter with its largest 4 (out of 67? ) moons. The moons as discovered by Galileo were known as Callisto, IO, Europa, Ganymede. IO is volcanic with fatal levels of nuclear hazard on its environment while Europa is Icy. Today, the phenomenon of aura produced on Jupiter’s moon Europa, was explained briefly. Click on preceding link.
Galileo had observed the 4 largest moons, as named above, with his small telescope which is today known as Galileo, which was only the 2nd ever made telescope in the history of humanity, with about 30 times more resolving power than the first ever made by an engineer from Netherlands.
( — need to check on that specification of “30 x resolving power” in units of telescope resolving power of 1st )
All in all, safely, only 2013 saw 50,000 people who followed and endorsed my online presence or who accessed my website contents. (since you can like a page once only using your f-b id and since website visits checks unique IP address, this is a unique individual stats, that is , most precise count of number of people)
#mdashf wants to offer its long felt gratitude. This was possible only because of goodwill of people. There was zero amount of publicity expenditure. Not a single dime was ever spent by me or to my knowledge anyone else towards publicity. I am open to generous grants by individuals or orgs, btw, if you want to support #mdashf. The only expenditures that were incurred was on website layout, theme, fonts, hosting charge etc and the use of fancy all-in-one computer, personal laptop and printers/scanners and yea: BSNL ISP More…
Fly through the mist .. we are looking for no priest. More…