Introduction

Introduction

In order for an LED based Entertainment Automated wash Light to successfully challenge conventional Automated Lights two things are required; a range of colours, including whites, and a beam angle remotely adjustable from the console to match those available on pre-existing Automated wash lights.

Lighting Designers have no interest in taking backward steps; new technology has to move forwards in new directions.  The beam angle adjustment technology outlined below does exactly that, literally creating a new direction.

LEDs and Colour

Current RGB or RGBA LED sources do not create the range of colours available in existing Automated Lights.  An obvious solution is to use a broader range of LED source colors similar to those in the Rainbow; Red, Orange, Yellow, Green, Blue, Indigo and Violet.  This translates passably enough into Lumileds’ Red 626nm, Red/Orange 617nm, Amber 590nm, Green 530nm, Cyan 505nm,  Blue 470nm and Royal Blue 455nm.  The availability of these LED wavelengths was disclosed in the original Lumiled document AB 11 dated February 2002.

What is helpful about these wavelengths is they are contiguous and cover the visible spectrum evenly. Consequently when combined they create light with a high Colour Rendering Index.

Orblite has demonstrated a working prototype using the above Lumiled LED wavelengths showing the wide colour range this technique creates. Drg 5 and Image 22

LED Beam Angle Adjustment

None of the current LED based lights have remotely controlled beam angle adjustment.  A conventional white light source contains a continuous spectrum of wavelengths and when a zoom lens is used to widen or narrow the beam chromatic aberration in the lenses can cause red and blue colour fringes.  The lens refracts Red, Green and Blue light by differing amounts and spreads the image out. Normal lenses are also designed to work with single sources – not multiple sources as you get with LED fixtures.

These effects are greatly increased when RGB light sources are distinct and greater still with an increase in the number of sources present.  Existing LED units try and get around these problems using manually changeable lenses, typically with some frost to help merge the colours together.  Applying another lens to ‘zoom’ the beam angle narrow to wide creates further problems and the result is a muddy badly homogenized beam.

An answer is to not use a lens system at all. One way of thinking of this is the difference between a human eye, a simple lens system, and an insect eye, a compound lens system. 

If you haven’t looked at the video on the visuals page it is suggested you do so before continuing.

Beam Angle

Changing The Beam Angle

Fig A and Image 8 and Image 9 show the important components

To go from a Narrow beam to a Wide beam we use a pair of Formers with Cam slots cut into them. Former B is an exact but flipped copy of Former A. The ends of the Eyes fit into the open square formed by the overlapping cam slots. See Image 15 and Image 4

Fig B shows the overlapping squares in the Narrowest beam mode. The composite beam has the beam angle of each individual Eye beam.

Fig C shows that the overlapping squares formed by the Cam slots have moved inwards, dragging the ends of the Eyes with them to form a wide beam. In this particular design Wide angle is created by rotating each Former by 8 degrees. Fig D and Image 10 show the 45 degree maximum beam angle if the individual Eyes have a 15 degree beam angle.

Formers could rotate further and the Ends could be pushed to a limit defined by the end of each Cam slot. This would create a beam look where the composite wide beam shown would separate into its seven component beams. This effect is currently referred to as ‘spiky’.

As well as creating a lens-less zoom the pair of Formers can be moved together in any direction to change the direction of the composite beam relative to the Top Plate.

Image 12, Image 11, Image 13

The movement shown in Fig E is called Beam tilt as it is in the same direction as real tilt. In this outline design the beam has tilted by 22.5 degrees. A more extreme angular deflection for some of the Eyes is shown in Fig F.

Image 16, Image 17, Image 18, Image 19

Movement of the pair of Formers in a direction at 90 degrees from that required for Beam tilt will produce a ‘Sweep’ of the beam along the tilt axis, similar to that caused by a Yoke Pan move. This is shown in Narrow beam mode in Fig G and Image 21

Sweep in wide angle mode is shown in Fig H.

Other beam movements are available by moving the pair of Formers relative to the Top Plate such as diagonal and circular beam movements. Fig I,

Image 3, Image 20.

Any of these movements can be achieved at any beam angle. It is also possible to create beam movements which do not pass through centre such as a square movement. Pretty much any desired beam movement can be created.

There are many interesting movement possibilities, including beam movements combined with yoke movements creating extremely fast moves.

We will not go into the Yoke movements available via the Orb yoke in this document (for those movements see the Orb video, in the Orb visuals page).

There is one further beam ‘width’ movement possible called ‘Flower’ Image 23 where both Formers rotate together in the same direction. This pivots the outer individual beams at right angles to the radius. When in narrow mode this has the effect of producing a wider beam angle as the Eye on one side of centre pivots one way and the opposite Eye pivots the other. When Flower is used in Wide angle it creates a Super wide Spiky look. Rotating A+B back through the normal setting through to the other direction will produce an interesting and unique effect where the beam narrows as the Formers rotate through ‘normal’ orientation and then widens again.

Flexibility

Colour & Intensity

The beam angle adjustment techniques described here and in the associated Patents assume that LEDs, whilst continuing to increase in light output, are not as bright as a single source and so a multiplicity of LEDs is required.  The individual beams making up the composite beam can be manipulated relative to each other and relative to the Top Plate.  This means colours and intensity can be individual as well.

Image 5, Image 6

The video shows a unit with 7 Eyes and each Eye has 7 different wavelength LEDs.  Every Eye can output a colour which is different from its neighbours.  This level of individual control would require 49 control channels if driven conventionally.  Patent GB2379100 describes a method whereby this can be reduced to 3 DMX channels.

Alternative Circular layouts

The video shows a 7 Eye configuration as this is the simplest practical lighting unit.  The next sizes for curcular arrays use 19 and 37 Eyes. An example of the Formers for a 19 Eye configuration is shown in Fig J.

The inner ring of Cam Slots are at a different angle to the outer ring of Cam slots as the inner ring has to travel a lesser distance for a move from narrow to wide beam, see Fig K.

In any configuration the Cam slots can be angled to create the required outcome, so an oval narrow beam to wide beam is possible.

Semi-Automated Light and layouts

A number of existing LED units could benefit from the addition of beam angle adjustment.  These include LED Pars, 8 lites or 9 lites and could also include the now ubiquitous Battens.  Adding remote beam angle adjustment would turn them into semi-automated lights as both tilt and pan movements can be achieved without a yoke along with narrow to wide beam angle adjustment and other beam movements.

Exactly the same principles can be applied to a square or rectangular array as to a circular one. Fig L. shows a 12 Eye Square configuration.

The beam width is spread in one direction, across the page, as the Formers are moved in opposing directions.

With beam direction, the same principle as before is applied and both Formers can move together, see Fig M, where they have moved page left.

And as is the case with a circular array any direction is possible so the circular motion of an essentially square beam is possible.  The Flower movement can also be achieved by rotating the pair of Formers.

For an explanation of how beam angle adjustment works for a Square or Rectangular array in the other direction to that shown in Fig L, see the explanation and Figs 49-52 in Continuation in Part US2006/0023461 available on the patents page.  Suffice to say here that it can be done.

Final Thoughts

Other Design Parameters

For a circular array Formers A & B can be driven by one motor; edge driven or through worm driven tabs.  The motor would logically travel with the Formers chassis.  The directional movement of Formers A & B is best achieved using a third device not shown in the Video.

One possible method is to have a quadrant rail attached to the inside of the body.  A post is attached to a slider which meshes with the quadrant rail via a motor which can position the slider anywhere in the quadrant.  The Post is attached at the other end to the centre Eye End Extension and its length can be shortened or extended via a motor and worm gear.  This then allows the centre End to be positioned anywhere desired.  Whatever the final design two motors are required for directing the beam.

It is likely that a Fan will be required.  To maximise airflow from the back of the light flowing over the Heat Sinks the less material required for Formers A & B the better.  Formers A and B are identical to manufacture and can be stamped out.  The internal edges of the cam slots are bevelled.   A ‘skeletal’ design for a Former is shown in Fig N.

Skeletal designs for square or rectangular arrays can follow a similar design pattern.

The Body shown in the early Figs is a truncated sphere and a clear or slightly frosted cover over the array of Eyes could be added, alternatively the front of each Eye could be fitted with a rain/UV cover.  There is no particular reason for using a spherical Body as the design is not constricted by the need for lenses.  The move to an LED based Automated Light will likely mean a move away from metal and towards moulded plastic.  The Body as shown could be formed in two halves with the Fan Cage hinged to facilitate cleaning the air filter.  An LED Automated Light of this type will be considerably lighter than a conventional Automated Light.

We are in an era of recycling and energy conservation.  LEDs are intrinsically (and increasingly) energy efficient in producing light and considerably outlast conventional light sources, so the other aspects of the design should also follow energy efficiencient and recycling parameters.

You may have noticed there is a 30 degrees difference between the orientation of the Eyes as shown in the Figs to that shown in the Images and Video.  Both orientations are possible.

Creating new LED Lights which have remote beam angle adjustment using this patented design requires a licensing arrangement for the relevant patents to an Entertainment Lighting company that has the R&D strengths to develop the above ideas into new products; and we do need new products.

© Richard Knight 2006