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The speed of the holographic image deblurring method(Ref.1-4) has recently been further enhanced by a new speed in the realization of the powerful holographic image-deblurring filter. The filter permits one to carry out the deblurring, in the optical computer used,in times of the order of 1 second, in contrast to times of minutes ,and sometimes hours ,which would be required for the enhancement of similar photographs with methods using microdensitometer scanning,encoding and digital electronic computing, even with the fastest and most powerful electronic computers. The newly developed method for rapid realization of the 'extended-range high-resolution holographic image-de-blurring filter'(Ref.5)permits one to make the filter,by means of the photo-holographic method used,in less than a single day's work,starting from the point-spread function(impulse response function),rather than in months required in earlier forms. Several filter realization methods have been developed(Ref.1-7),one of which is made possible by a suitable combination of digital electronic computation of the 'impulse response function' [for cases when it may be derived by analysis ]and its 'photo-holographic'realization in the form of the 'holographic Fourier-transform division filter'(Ref.1,2),In this way we take advantage of the very fast optical computing for the deblurring(compared to much longer digital electronic computing times), while using the digital computer for the part of the filter computation in which it is very rapid. The experimental achievements using the holographic image-enhacement method will be illustrated with examples ranging from out-of-focus or motion-blurred photographs, including 'amateur'photosrecorded on POLAROID film, to the shar-pening of the best available electron micrographs of viruses, obtained from the most powerful scanning electron microscope(Ref.8),In one case, the method has permitted us(Ref.9)to resolve a long-standing biophysical controversy (Ref.10) by revealing the double-helical coiling of a filamentous bacterio-phage(fd) virus specific to E.coli (Ref.11) and by showing that only a portion [rather than perhaps the entire virus, as previously assumed according to some studies(Ref.12)]did in fact seem to take on the double-stranded structure. Images recorded with X-rays, notably from rocket-borne photos of the Sun, and out-of-focus photographs from ca-meras in NASA satellites have been similarly deblurred(Ref.13), and other among the many applications include the sharpening of images in ultrasonic imaging, beyond the ultimate as previously limited by the instrumental limitations themselves.
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