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Characteristics of Intelligent Luminaires

Beam Size and Light Distribution

Beam Size and Light Distribution

One of the requirements of moving luminaires is the ability to control the size of the beam and the light distribution - hard edged or diffused.

Beam size can be controlled by two different methods:

Iris diaphragm mask:

The iris is built into the optical system, and opening and closing the iris diaphragm changes the diameter of the light beam. The intensity of the beam remains constant regardless of the diameter of the iris. When used in combination with gobos, the edges of the gobo will be revealed as the iris opens and cut off as it closes . This method is the same as that used to control the beam size of most follow-spots and some profile spots.

The Iris system of the SuperScan Zoom by Clay-Paky.

Variable lens optics:

A variable lens system is used to concentrate the light into a smaller beam much in the same way as in a variable or zoom profile-spot.

The smaller the diameter of the beam, the more concentrated the light will be. An iris is used in addition to the variable lens system and its movement has to be synchronized with the lens movement.

The optic zoom system of the SuperScan Zoom by Clay-Paky.

The variable lens mechanism of the SuperScan Zoom by Clay-Paky.

The variation of lighting distrubition of the super scanzoom by Clay Paky.		The remote control shutters of the PAL by Martin
The distribution of the light beam, i.e. the effect of hardening and softening of the beam edge can be achieved either by inserting a frost filter or by moving the lens in or out of focus.		One of the newest options introduced into intelligent luminaires is gate shaping by controllable shutters and iris diaphragm, which allow shaping the gate in much in the same way as a profile spot do (5) . . This feature, along with the option of using tungsten light sources, has increased the popularity of intelligent luminaires in theatre. These luminaires can now seamlessly be integrated into any conventional theatre lighting design serving not just for specials and effects but also as part of the general lighting.