Showing papers on "Contrast transfer function published in 1985"

Back-illuminated CCD imager adapted for contrast transfer function measurements thereon

Abstract: Stripe patterns of varying spatial frequency, formed in the top-metalization of a back-illuminated solid-state imager, facilitate on-line measurement of contrast transfer function during wafer-probe testing. The imager may be packaged to allow front-illumination during in-the-field testing after its manufacture.

Method of measuring spherical aberration and apparatus therefor

Abstract: An optical testing method and apparatus employing a non-interferometric technique, making use of axial intensity information, in which the intensity of the light pattern along the optical axis is calibrated to achieve improved measurement of spherical aberration.

The use of histograms for transmission electron microscopy: defocus and astigmatism correction at high resolution

Abstract: A real-time method for optimizing the defocus of a conventional transmission electron microscope in the phase contrast imaging mode has been investigated using image histogram data. This method can also be used to minimize the objective lens astigmatism. It will be shown both theoretically and empirically, using a digital television frame store, that a histogram will give the largest peak when an image has a broad and flat contrast transfer function. This method has distinct advantages of speed and minimal computational requirements over obtaining the power spectrum of an image.