We use cookies to distinguish you from other users and to provide you with a better experience on our websites. Close this message to accept cookies or find out how to manage your cookie settings.
We use cookies to distinguish you from other users and to provide you with a better experience on our websites. Close this message to accept cookies or find out how to manage your cookie settings.
Published online by Cambridge University Press: 31 January 2011
In the 1920s Vasco Ronchi developed the well-known method of testing optical systems now named after him. The essential features of the Ronchi test may be described by reference to Figure 44.1. A lens (or more generally, an optical system consisting of a number of lenses and mirrors) is placed in the position of the “object under test”. The lens is then illuminated with a beam of light, which, for the purposes of the present chapter, will be assumed to be coherent and quasi-monochromatic. These restrictions on the beam may be substantially relaxed in practice.
The lens brings the incident beam to a focus in the vicinity of a diffraction grating, which is placed perpendicular to the optical axis, i.e., the Z-axis. The grating, also referred to as a Ronchi ruling, may be as simple as a low-frequency wire grid or as sophisticated as a modern short-pitched, phase/amplitude grating. The position of the grating should be adjustable in the vicinity of focus, so that it may be shifted back and forth along the optical axis. The grating breaks up the incident beam into multiple diffracted orders, which will subsequently propagate along Z and reach the lens labeled “pupil relay” in Figure 44.1.
The pupil relay may simply be the lens of the eye, which projects the exit pupil of the object under test onto the retina of the observer.
To save this book to your Kindle, first ensure [email protected] is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Find out more about the Kindle Personal Document Service.
To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Dropbox.
To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Google Drive.
