Available online
Description
The programme examines the three basic techniques involved in microscopic imaging; bright field, dark field and phase contrast.
The programme examines the three basic techniques involved in microscopic imaging; bright field, dark field and phase contrast.
| Module code and title: | ST291, Images and information |
|---|---|
| Item code: | ST291; 08 |
| First transmission date: | 09-06-1977 |
| Published: | 1977 |
| Rights Statement: | |
| Restrictions on use: | |
| Duration: | 00:24:15 |
| + Show more... | |
| Producer: | Ted Smith |
| Contributors: | Stuart Freake; Alan Walton |
| Publisher: | BBC Open University |
| Keyword(s): | Microscopes; Microscopic |
| Footage description: | Shots of human cheek cells under the microscope set for phase contrast. Alan Walton introduces the programme. Stuart Freake sets up the optical bench to develop a system for making phase objects more visible. Alan Walton uses a computer to calculate the field of light on the output side of the basic object on the bench. The results are displayed on an oscilloscope. Stuart Freake goes on to demonstrate, using the equipment on the optical bench, how the field of light propagates. Walton does the same using the oscilloscope screen. Freake adjusts the optical apparatus so that an image of the object is projected on a screen. In fact he has constructed a simple microscope but one in which the phase information is difficult to see. Alan Walton summarises Stuart Freake's experiment with the aid of an oscilloscope screen display. Walton next explains the principles of dark field microscopy. He uses an oscilloscope display to help make his points. Stuart Freake, again using the optical bench apparatus, demonstrates that, by spatial filtering, phase information is converted into intensity information. Alan Walton looks at several microscopes ranging from a replica of Robert Hooke's seventeenth century microscope to a modern instrument. He particularly examines the lighting system used in each. Tony Woolgar explains the principles behind illumination systems in modern microscopes. He uses several diagrams to make his points. Woolgar shows how both bright field and dark field systems are implemented. Alan Walton, with a modern microscope, looks in detail at its lighting system. Shots of human cheek cells under dark field magnification. Commentary by Tony Woolgar. Stuart Freake uses the optical bench apparatus to demonstrate phase contrast microscopy. Alan Walton explains the principles behind phase contrast microscopy. He uses an oscilloscope display to help make his points. Tony Woolgar, using a diagram and a microscope, explains how phase contrast is implemented in a practical microscope. Shots of human cheek cells under phase contrast magnification. Alan Walton sums up. |
| Master spool number: | DOU2468 |
| Production number: | FOUS729P |
| Videofinder number: | 2119 |
| Available to public: | no |
