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1. The third dimension - This band was originally a transmitted television programme, ST291/9. In this band Dr. Keith Hodgkinson of the Open University examines the three dimensional images produce...d by holograms. It is chiefly concerned with the possibilities of holography as a medium for display and illustration. The band begins with an experiment which shows the microscopic interference fringes of coherent light which form the basis of holography. At Loughborough University Dr. Hodgkinson looks at some remarkably high quality holograms and shows the layout for their recording. The last section of the band examines holograjpis that can be viewed in ordinary white light (i.e. a light bulb) and a method for incorporating movement into holographic images. -- 2. Holography at work - This band was originally a transmitted television programme, ST291/10. This band is about the use of holographic interferometry to record minute surface deformations on objects and in particular the use of this technique to study vibrating objects. Dr. Keith Hodgkinson of the Open University starts the programme at Loughborough University where he shows interference fringe in real time produced by one of the holograms seen in the previous programme. Dr. Hodgkinson and Dr. Stuart Freake demonstrate and explain an experimental set-up which is used to study the vibration of loudspeakers using holographic interferometry, both 'time averaged' and 'stroboscopic'. The programme concludes with an explanation of the speckle effect which is produced when laser light illuminates an object and an example of how it can be used to produce interferograms. -- 3. Lens design - This programme was filmed on location at a specialist manufacturer of lenses. It features two lenses requiring different performance criteria, (a) a small collimating lens for use with a CCD camera and a solid state laser 'point' source of illumination, and (b) a larger aperture lens for use in a photocopying application The designer, Dr David Stephenson, discusses how each design was specified and optimised using either Optical Transfer Function (OTF) or Modulation Transfer Function (MTF) performance criteria. The role of computers in aiding the design process and testing of the final lens assembly is highlighted and all the most important stages of manufacture and assembly are shown. -- 4. Viewing the invisible - This programme shows the essential features required to image so called 'invisible', transparent 'phase' objects, using an optical microscope. Dr Peter Evennett, secretary of the Royal Microscopical Society, uses his specially adapted microscope to show how placing objects (amplitude or phase spatial filters) in the back focal plane of the objective, the transform plane, can dramatically improve the contrast in the image plane. Two small CCD television cameras and a split screen technique show what happens simultaneously in both planes as Peter demonstrates different ways of manipulating the image by selectively blocking some of the light passing through the transform plane of the microscope.
Metadata describing this Open University video programme
Module code and title: ST291, Images and information
Item code: ST291; VCR2
Published: 1993
Rights Statement:
Restrictions on use:
Duration: 01:31:43
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Track listing:
track listing for this programme
Track 1 1. The third dimension
Version note: This band was originally a transmitted television programme, ST291/9
Track 2 2. Holography at work
Version note: This band was originally a transmitted television programme, ST291/10
Track 3 3. Lens design
Producer: Tony Jolly
Contributors: Peter Evennett; Keith Hodgkinson; Andrew Norton
Publisher: BBC Open University
Keyword(s): Coherent light; Hologram; Laser
Master spool number: DOU8173
Production number: FOUS807W
Videofinder number: 4969
Available to public: no