Applied Science - Technology (5A)
Post Lab

  • Exploring the uses of lasers.
  • Predicting future use of laser technology.


  • hologram
  • laser
  • Internet
  • holograms (green, red, etc)
  • worksheet

Students research the uses of lasers in our society.

Surgery using a laser


The list of practical applications for the laser is growing rapidly. Laser's properties have practical uses in measurement and are used by many people from surveyors to machinists. When engineers were constructing the Bay Area Rapid Transit system, lasers were used to line up the dredging equipment for the underwater tunnel in San Francisco Bay. Laser beams have also been bounced off reflectors on the moon to provide information about the movement of the Earth's crust. Eye surgeons use lasers to "weld" detached retinas back into place without making an incision. The laser is simply brought to focus in the region where the welding is to take place. Lasers are used to measure the speed of light in a laboratory. They can also measure distances on a street or movement along an earthquake fault. In grocery stores, the bar code pattern is read by a laser to decode the price of the product. Nearly all major sewer pipe and storm drain pipe installations are aligned using helium-neon lasers. In the auto business, lasers are used for wheel alignment. In biology, lasers are used to measure blood cell diameter. The applications are unlimited.

Lasers are also used to make holograms. Holograms are three-dimensional pictures, which when illuminated, produce images so realistic that the sides of objects can also be seen. Let students observe how a hologram is made when laser light is used to take a picture of an object. Laser light is projected on a photographic plate to produce these images.

Helium-neon lasers are the cheapest visible light presently available and is used in a supermarket scanner. The laser is scanned across a bar code on a package which is detected by the laser as 0 and 1. This is a language the computer (cash register) can interpret to represent the price of the package. Semiconductors are also used to produce lasers with invisible light. Home entertainment systems use the optical disc to provide digital audio or video signals. Information is stored by using a laser beam to punch a series of holes in reflecting layers. In the disc player, a semiconductor laser output is reflected from the disc to a detector. The pattern of holes is converted to a digital signal that contains the coded audio information. Semiconductors also are used in laser printers. Carbon dioxide lasers are used for cutting and heating. Argon lasers are used in the medical profession.


  1. Show students the different holograms. These were all created by different lasers. If you view them in natural light, the holograms stand out more.
  2. Talk about the uses of lasers. Lasers are used in the grocery store to cutting steel. Use the Internet to search for companies that use or produce lasers. Search under "laser" for general information in the "adult" search engine, like Students will find a host of products that use laser technology. Have them list the products that they find on the worksheet. Laser technology changes rapidly, with new products being developed all the time. Make students as familiar with lasers as you can. They are in your students' future.
  3. On the worksheet it shows the how lasers are used in making holograms, which is just a "3D" picture on a piece of holographic film. Taking the picture is more involved than using a camera. The laser helps to define the object better. Show students the different holograms, which are created through different film.

Laser laboratory

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