Technological progress supplies us with unusual things and holograms are a good example. Scan the text to find answers to these questions.

1. What is the difference between holography and a hologram?

2. Who discovered the holographic effect?

3. How was the word hologram coined?

4. What was the aim of Dennis Gabor's research?

5. Was the aim achieved?

6. Why were first holograms imperfect?

7. When was the first laser operated?

8. What are the basic types of holograms?,

 

Read the text attentively to learn more about holography.

Holography and Holograms

History. Holography and hologram are normally referred to as a process and as a plate or film itself respectively. In 1947 Dennis Gabor (the father and the first theorist of holography, awarded with the Nobel prize for his research) coined the term hologram from the Greek words 'holos' meaning whole or complete and 'gram' meaning message. Gabor's theory was originally intended to increase the resolving power of electron microscopes. Incidentally, it was proved not with an electron beam, but with a light beam. The result was the first hologram ever made. Gabor's hologram was clear, but imperfect, as he lacked the correct light source - the LASER, which was first seen operating in 1960.

Types. The latest achievements in laser technologies being applied, holography has developed considerably. Numerous types of holograms can be noticed operating everywhere. The following are considered the most frequent:

transmission holograms. They are viewable with laser light when

both beams approach the film from the same side;

reflection (white-light) holograms. These are viewable with white

light from a suitable source (spotlight, flashlight, the sun, etc.)

when both beams approach the film from the opposite sides;

multiple-channel (rainbow) holograms. These holograms with

several images are not only visible from different angles; they also

change colour at each new angle;

real-image holograms. They produce the image in front of the plate

towards the viewer. Most holograms in holography museums are

of this type.

Application. Holography being an art that attracts people's attention and curiosity, colourful multidimensional images are widely used in advertising, stamps, jewelry, with holography museums exhibiting masterpieces. Credit cards are considered original if supplied with a hologram. Holographic lenses are lighter than traditional lenses and mirrors and can be designed to perform more specialized functions, for instance, to make the panel instruments of a car visible in the windshield in order to increase safety. Holographic interferometry (a very precise technique used for measuring changes in the dimensions of an object) is widely used in industrial stress analysis and quality control. The list of applications may be continued indefinitely.

Match the following noun compounds with their Ukrainian equivalents.

1. laser beam а інтерференційна картина

2. beam splitter b) промінь лазера

3. reference beam с) роздільник луча

4. object beam

5. interference pattern d) опорний промінь

e) об’єктний промінь

Write a 'How to Make a Hologram' guide for those who want to create holograms at home. Cover the following questions.

1. What is a hologram?

2. How is it created?

3. What special equipment is necessary?

4. What must everyone remember while making a hologram?

5. Where can holograms be applied?

You can start like this:

1. A hologram is a three-dimensional image. It is created when laser

light...

2. To produce a hologram at home...

3....

 

Insert the necessary prepositions.

1. I'm going to study the properties... some materials.

2. Julia is interested... elasticity.

3. Steel tools have grown... popularity.

4. The student plans to carry... his research on materials engineering.

5. We use metals... different engineering purposes.

6. Steel may be pressed... a new shape.