The resolution of an optical imaging system – a microscope, telescope, or camera. Why Do They Say We Are Limited, Optics Wise? What Are Difraction Limits? Hubble is a non optical limited Telescope always working at their maximum Difraction Limit.



The resolution of an optical imaging system – a microscope, telescope, or camera – can be limited by factors such as imperfections in the lenses or misalignment. However, there is a fundamental maximum to the resolution of any optical system which is due to diffraction. An optical system with the ability to produce images with angular resolution as good as the instrument’s theoretical limit is said to be diffraction limited.
The resolution of a given instrument is proportional to the wavelength of the light being observed, and inversely proportional to the size of its objective. For telescopes with circular apertures, the size of the smallest feature in an image that is diffraction limited is the size of the Airy disk. As one decreases the size of the aperture in a lens, diffraction increases. At small apertures, such as f/22, most modern lenses are limited only by diffraction.
In astronomy, a diffraction-limited observation is one that is limited only by the optical power of the instrument used. However, most observations from Earth are seeing-limited due to atmospheric effects. Optical telescopes on the Earth work at a much lower resolution than the diffraction limit because of the distortion introduced by the passage of light through several kilometres of turbulent atmosphere. Some advanced observatories have recently started using adaptive optics technology, resulting in greater image resolution for faint targets, but it is still difficult to reach the diffraction limit using adaptive optics.
Radiotelescopes are frequently diffraction-limited, because the wavelengths they use (from millimeters to meters) are so long that the atmospheric distortion is negligible. Space-based telescopes (such as Hubble, or a number of non-optical telescopes) always work at their diffraction limit, if their design is free of optical aberration.
The beam from a laser with near-ideal beam propagation properties may be described as being diffraction-limited. A diffraction-limited laser beam, passed through diffraction-limited optics, will remain diffraction-limited, and will have a spatial or angular extent essentially equal to the resolution of the optics at the wavelength of the laser.

Author: Bruce Swartz Astronomer

Hello I am studying Astro Physics, Astronomy and the stars. Planets, Celestial bodies like Asteroids and Comets. Deep sky (Messier Objects) I have a unique technique in editing and capturing planets both far and near. My name is Bruce Swartz. I am An Amateur Astronomer...Welcome.

6 thoughts on “The resolution of an optical imaging system – a microscope, telescope, or camera. Why Do They Say We Are Limited, Optics Wise? What Are Difraction Limits? Hubble is a non optical limited Telescope always working at their maximum Difraction Limit.”

  1. In other words. That LIMIT we all are used to hearing about. That Theoretical Optical evaluation I always say is limited to it’s own instrument and the light intake. The More light that is gathered and the brighter the regions. The more we will get an image but the atmosphere so long me will always be a factor. It’s a waiting game to wait for the right moment to get a certain constellation. At times all we see is dust and other times a clear heavenly image.

    Like

      1. Thanks for coming back my friend. I greatly appreciate you doing so. Welcome AGAIN back. loll Have an awesome day.

        Like

  2. Hi great blog! Does running a blog such as this take a massive amount work? I have absolutely no understanding of computer programming however I was hoping to start my own blog in the near future. Anyways, if you have any recommendations or tips for new blog owners please share. I know this is off subject nevertheless I just needed to ask. Appreciate it!

    Like

Give Feedback Here

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

w

Connecting to %s