Images(2)

early laser

Datecirca 1962

Inventory Number1997-1-1583

ClassificationLaser

Subject

Maker Nicolaas Bloembergen born 1920

Cultural Region

Place of Origin

Dimensions19 x 31 x 19 cm (7 1/2 x 12 3/16 x 7 1/2 in.)

Material

DescriptionThe instrument sits on an aluminum base, which is itself supported by another slate of aluminum. The whole instrument pivots on that slate. The instrument is cylindrical in shape. Four connectors, powering the laser, comes out from each side. They are partly covered in glass. On top, two tubes are used to make vacuum or inject gas inside the resonant cavity. Both mirrors are missing. (This laser was most likely based on a gas rather than a crystal.) Curved wires covered in rubber link connectors between each others. Two vertical frames keep the laser upright and stable.

In Collection(s)

Exhibit 2005--CHSI's Putnam Gallery

Signedunsigned

Inscribedon side of base: TRIGGER / SETTING-20

FunctionThe material that produces laser light are most commonly based on a crystal or a gas. When this medium is stimulated by an electrical current, for instance, it starts absorbing energy, exciting the states of the particles composing the medium. This all happens within what is called a resonant optical cavity, a specially designed chamber made with a mirror at one end and a semi-silvered mirror at the other. The photons, produced by the excited particles, are trapped inside this cavity, reflected back and forth by the two mirrors. Each pass they do creates more photon, hence the energy of the light increases. When the energy peak is reached (or saturated), that light becomes a laser of a specific wavelength. It goes out from the side of the semi-silvered mirror.

ProvenanceFrom the Department of Physics, Harvard University.

Historical AttributesNicolaas Bloembergen shared the 1981 Nobel Prize in physics for the development of laser spectroscopy. He also developed the theory of non-linear optics to help explain how the intensity of laser light affects matter. See the <a href="http://nobelprize.org/nobel_prizes/physics/laureates/1981/bloembergen-autobio.html" target="_blank">Nobel Prize website</a> for more information on Bloembergen and his work. An interview of him can be seen <a href="http://vega.org.uk/video/programme/27" target="_blank">here</a>.