Laser harp

Jarre playing the laser harp

A laser harp is an electronic musical instrument consisting of several laser beams to be blocked, in analogy with the plucking of the strings of a harp, in order to produce sounds. It is famously used by Jean-Michel Jarre in his concerts.

The term "laser harp" and the first working laser harp was invented and made by Geoffrey Rose in 1976. The first model was constructed with a matrix of 5 X 5 laser beams in an octagonal frame. It has subsequently been used in a number of different designs, including a MIDI version invented by Philippe Guerre, and a recent one created by Yan Terrien. They have also been used in public art installations such as those created by Jen Lewin on display at Lincoln Center in 2000 and Burning Man 2005.

Design

A laser harp is generally built using a single laser, splitting its beam into an array of beams in parallel or fan arrangement. When a beam is blocked, this is detected by a photodiode or photoresistor, which is connected to electronics activating the relevant note. Playing the actual sound is usually handled by connecting the laser harp to a synthesizer, sampler or computer.

The laser harp may be framed or frameless, the framed type using an array of photodiodes or -resistors inside the upper part of the frame to detect blocking of the laser beams. The frameless design is somewhat more elaborate, relying on the light being reflected back from the blocking object into the beam-splitting arrangement.

Safety considerations

In order to produce laser beams visible in normal air, a relatively powerful laser is needed; at least about 20 mW of power, depending on the type of laser and the design of the instrument, is required in order to produce a visible array of beams. However, a considerably more powerful laser is needed to yield spectacular results, generally 500 mW or more. In any case, class IIIb or IV lasers will usually be necessary, introducing a significant risk of skin and eye damage unless precautions (gloves and protective glasses) are taken.

Use in Jean-Michel Jarre concerts

The laser harp is one of the most famous instruments used by Jean-Michel Jarre in his concerts. First created by Bernard Szajner for The Concerts In China tour, the laser harp is used in almost every concert for playing the second part of Second Rendez-Vous and in other songs as well (it usually appears two or three times in a concert).

The laser harp was not used on his Aero concert but it was revived in 2004 and has been used since then, mostly on his tracks Second Rendez-Vous and Chronologie Part 3.

Although the laser harp makes no actual sound itself, (merely triggering a note on a synthesizer) Jarre has consistently used it to trigger a particular sound which has become synonymous with his use of the laser harp, which is based on a preset from the Elka Synthex synthesizer.

Many people suspect the laser harp, as well as some other custom instruments, is a fake, but this is not always the case. The laser harp has been proven to work and has been played by Jarre live occasionally, especially on his 1997 concert tour and Oxygen in Moscow. Other notable live playings of the harp occurred during Chronologie 3 at Beijing as well as at Hymn to the Akropolis and during Calypso 2 at Paris La Defense. In the European Tour 1997 Jarre played Laser Harp for the first song on that concert, the famous first notes of Oxygene VII, played three times without any other instrument or sound.

However, the harp at the Manchester venue of the Europe in Concert tour was certainly fake, as the laser failed during the performance but the lead line, actually played on stage by Francis 'Bunny' Rimbert, continued.

See also

• Laser safety
• Laser lighting display

External links

• The Laser Harp Pages
• Guide to creating your own laser harp
• Recent laser harp projects by Blueink Studios