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Lighting incorporated into costumes and props can be achieved in many different
ways. It can be very subtle, such as with a glowing back-lit control panel, or dramatic,
such as with neon or strobes. Some examples of these are shown below.
| Light Emitting Diodes (LEDs) |
| LEDs come in a variety of packages and colors, and may even have blinking circuitry
built into the diode assembly. Except with the blinking versions, a current-limiting
resistor should be placed in the circuit to prevent damage or burning out the LED during
use. While you can precisely calculate the resistor value to use, the only real reason for
doing so would be to achieve maximum brightness of the LED when used at a specific
voltage. If your power source is batteries, the resistance should be calculated for the
maximum voltage that might be encountered, either when using fresh batteries, or during
charging if you are using NiCd or other rechargeable batteries. For voltage ranges from a
few volts to 15-20 volts, a resistor with a value of 4-500 ohms would be a good value. If
you will never exceed five or six volts, then a lower value can be used. I generally will
never use less than about 100 ohm resistors with low voltage circuits, such as the light
sabers. Blinking LEDs generally have an operational voltage range that should not be
exceeded to avoid damaging the LED and/or circuitry. Blinking LEDs are handy if you have
very limited room or if you only want a limited number of flashing LEDs in a particular
area. If you want to have several LEDs all blinking in sequence, then a blinking circuit
needs to be built or acquired. Most commercial blinking circuits seem to drive about 5
LEDs, although they may have multiple LEDs attached to the output. This allows your to
configure the flashes to radiate from a center point (5 flashes out in each direction), or
to run then end-to-end so that you have "chaser" LEDs where two LEDs are lit at
any given time. |
LEDs come in a variety of sizes, colors, and shapes. The four specs on the round disk
are surface-mount LEDs sitting on a button battery.
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| Incandescent lights |
| Incandescent lights are probably the simplest to wire and operate, however you must
take into account extra heat if it enclosed, possibility of the bulbs burning out, their
slightly fragile nature, and the issue of light and dark streaks due to irregularities in
the glass bulb or the reflector. All in all, I prefer to use LEDs when possible to avoid
most of these issues. However, for the Tick costume, I needed to have white eyes, and
wanted them to glow in the dim light. Incandescent bulbs provide this easily. To minimize
risk to jarring or burn-out, I mounted two bulbs in each eye. The bulbs were enclosed with
a curved metal surface behind them, and cut sections of white plastic soap boxes for the
eye itself. The thick white plastic gave a shiny white appearance in brighter lighting,
but the rear-mounted bulbs provided a diffused yellow-white light through the plastic
covers. |
Incandescent light bulbs are probably the easiest to wire, and since they produce a
full-spectrum white light, can be used with colored filters to achieve most any color.
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| Fluorescent lights |
| Fluorescent lights also require a power supply, and even though they can operate from
batteries, the battery power must be boosted by a small transformer circuit to several
hundred volts. At this voltage, the gas vapor inside the bulb will glow faintly, usually
in the ultra violet. The UV light excites the phosphor coating inside the bulb causing it
to glow. A standard white fluorescent bulb can be painted with a transparent paint or
covered with a colored plastic film to shift the color into about anything you want. An
ultraviolet bulb is basically the same construction, but the clear glass tube is tinted a
dark blue-violet. In my Chernobog costume, a white 6" fluorescent light is used to
illuminate the eyes. Pieces of yellow and orange film tint the light to the desired color.
Thin translucent plastic cut-outs are placed in the eye holes to diffuse the light even
more. The result is a uniform yellow to yellow-orange glow in the eyes, with none of the
glass or lens distortion that would be created using incandescent bulbs or LEDs.
I used an exposed 6" ultraviolet bulb in one of my early Blasters, creating a
weird blue-violet glow in the front barrel. The front end of the blaster has a strobe to
create a bright white flash when triggered.
My latest transparent light saber also has a small 2" UV bulb to make a blue glow
when it is active.
Miniature ultraviolet lights. The picture is slightly misleading, as the two small
tubes (one glowing) are filtered very well, and produce very little visible light.
The glow around the bulb is from laundry soap whitening residue left in the towel. The top
bulb is from one of the small "Magic Light" units. |
The circuit from a fluorescent light is a small inverter. It converts the battery power
from Direct Current (DC voltage) to Alternating Current (AC voltage), then steps the
voltage up by running the pulses through a transformer. The transformer circuit from a 6v
light is shown at the bottom, while a 3v transformer sits on the "magic light"
(actually it is a small fluorescent tube coated with dark blue-violet to block most of the
visible white light, but pass ultraviolet light.) The small black and silver block in the
upper left is an inverter circuit specifically designed for driving Electro-Luminescent
backlights. For small EL pieces, you can use one of the fluorescent supplies shown here.
 
Small neon bulbs can be powered from the same fluorescent power supply. The red neon
bulb is clear glass, show the typical red-orange glow of neon gas. The green
"neon" bulb uses a phosphor-coated glass. Neon gas gives off some ultraviolet
light, that will cause the phosphor to glow green. Small amounts of mercury can also be
used (usually with krypton gas) to create a blue-white glow, also strong in the
ultraviolet.
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| Electro-Luminescent lights |
| Electro-Luminescent lighting is similar to fluorescent, in that it needs high voltage
to light up. Generally, the same power source from a fluorescent light will operate small
Electro-Luminescent sheets without problem. If you want to create a project with both the
EL material and fluorescent bulbs, plan on two power supplies though. The bulb requires
you to ionize the gas across the distance of the two electrodes in either end of the tube.
EL lighting starts with a metallic back sheet, covers it with a porous phosphor material,
then covers this with a transparent layer that has a conductive film on the phosphor side.
When power is applied to the two conductive surfaces, the phosphor glows. But because the
distance between film is so much less than a tube, the EL material will light up, but not
your bulb if attached to the same supply. Unlike the bulb, EL material is available in
thin flexible sheet, tape form, and even "wire". Complete kits are available
from both electronics and hobby supply companies (EL Experimenter's kit) or direct from
the source, such as with Being Seen Technologies (on the Internet.) A recent addition to
the beingseen.com website is the addition of impact-resistant light saber kits using EL
tape enclosed in plastic rods or tubes (probably polycarbonite plastic.) While my neon
sabers are bright, they will not take any shock without shattering the fragile glass tube
inside. I used Electro-Luminescent film to light my creature's eyes in this year's
costume. If I found it back when I made Chernobog, I probably would have used it there
too.
Using a LimeLight EL panel with a small fluorescent power circuit, I added a pale blue
glow under the blue quartz crystals in my titanium broadsword. The titanium-coated quartz
crystals in the medallions on either side of the handle conceal the switch and batteries
to power it.
A composite image showing different types of Electro-Luminescent materials. A Lime
Light (night-light) is being powered from a 6v fluorescent power supply. (As were all of
the others, then the glow from each was superimposed on the image.) The red sheet in the
background is the EL sheet that was cut to fit behind the eye. |
EL Wires from Being Seen Technologies. These come complete with a small battery driven
power supply that can be switched to always on or flashing.
Electro-Luminescent sheet produces a uniform red glow in a creature's eye.
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| Neon |
| Neon requires even higher voltage than fluorescent bulbs. A small battery powered neon
power supply could generate close to 1000 volts. Like the fluorescent tube, the gas
between the two end electrodes must be ionized to glow. In my neon light sabers I chose to
use only clear glass tubes. This limits the color selection to two: neon gas will generate
a red-orange glow, and krypton and mercury vapor are used to create a pale blue glow. If
you use phosphor coated tubes, just about any color you want is available. Phosphor coated
tubs may appear white when off, or may have a dark, but transparent coating over the
outside of the glass to enhance the color or provide subtle tints not available with the
phosphor directly. My neon light sabers have the neon power supply wired to twin-ax
connectors to allow the neon blade to be removed for transport. Most neon tubes can be
connected by a single lead to the positive side of the power supply, using the supply like
a tesla coil. The problem I have seen is that the user becomes the ground at the opposite
end, usually resulting in a constant "tingle" where you are touching the metal
handle. To protect the user from being shocked, a very fine ground wire is run the length
of the tube and connected to the opposite end of the blade.
The mega-gun I created for my Dark Trooper costume used a short red-orange neon tube in
one of the side barrels. A super-bright orange LED in the tip created a "beam"
from the imitation laser. |
The inside of one of my neon light sabers. The neon supply is in the center, and
connects to the twin-axial socket at the business end of the saber. The power supply is
wired to 10 NiCd batteries that provide about 12v of power when charged. The toy
lightsaber circuit trips a relay that turns on power to the neon supply.
By adding a voltage regulator circuit between the batteries and the neon power supply,
the length of the neon glow can be adjusted. A small neon supply can power a 3-4' neon
tube without much problem.
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| Helium-Neon lasers (HeNe) |
| Adding helium to the neon gas shifts the color slightly more pink. Gas lasers, like
neon bulbs use very high voltage, but the power must be polarized just like a battery, so
that there are a positive and negative supply. Gas lasers use a tube that creates a very
narrow path down the length of the tube, and the electrical contacts are outside of the
path of the light. Mirrors attached to the ends of the tube reflect the light back and
forth between them, until it is bright enough to escape through the front mirror. The
front mirror has about a 5% transmission with 95% of the beam reflected back into the
laser. Laser supplies generally produce more power than neon supplies, and often cost
quite a bit more. HeNe laser supplies are available for battery powered operation if the
laser is small (usually .1mw or less.) Over a certain size, only 110 volt line current
power supplies are available. HeNe lasers generally produce a bright red-orange dot,
very similar to the LED lasers. I say generally, because there are also some
"exotic" color HeNe laser tubes available. Unlike LED lasers that only produce a
single wavelength of light, gas lasers often produce a mixture of light at different
wavelengths. The brightest wavelength produced with the helium-neon mix is bright red,
however there are also bright wavelengths of yellow, orange and green also produced by the
glowing gas. By using special filter coatings on the exit mirror, one of the other
wavelengths can be projected, by "blocking" the primary red and other lesser
colors. Because the secondary colors being produced are secondary, the intensity of the
laser at these wavelengths is much less. A .1mw green laser will typically use as much
power as a .5mw red laser (because it probably would be a .5mw red laser if this color was
not being filtered out.) As a result, you need a larger power supply to drive it, and most
battery powered ones won't do it.
My first laser pistol used a very small HeNe laser tube. This gives off a bright pink
glow when the laser is fired.
I also created a larger laser rifle, using a large HeNe laser in the barrel. Again,
this lights up bright pink when fired.
The Bryer pistol I created for my Dark Trooper costume also conceals a small HeNe
laser. |
HeNe (Helium-Neon) lasers require a filtered high-voltage power supply. Smaller laser
tubes can easily be powered from a 12v neon supply, but the larger tubes and fancy colors
of HeNe lasers generally require a 110v AC power supply. A variety of HeNe laser tubes are
show here, along with a 12v DC power supply (bottom left) and a 110v AC supply (bottom
right.)
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| Laser Diodes |
| Like LEDs, laser diodes operate on fairly low power that can be provided with
button-size batteries. However, unlike LEDs where a small resistor is all that is needed,
a laser diode requires a controlled power source. This is no longer a real problem for
those who are electronically challenged, as small laser pointers are available for well
under $10, and by ripping one of these open, you can get a laser diode and the necessary
power supply circuit. Removing the button switch or hard wiring it closed is a simple
matter, then by connecting the power contacts to your sound chip, the laser fires instead
of a flashlight bulb or LED. Laser LEDs are usually mounted in thick aluminum or brass
to help dissipate heat. The laser LED usually looks like a small transistor with a window
in the top, and can easily be damaged from static during handling, or from overheating
during use.
If you plan to use a laser LED in a project, try to plan a way that you can retain as
much metal around the LED for cooling. To extend the life of the laser, make sure the
laser diode has a way to radiate excess heat. |
Some examples of LED lasers. Laser pointers have dropped as low as $4-5 if you shop
around. Several years ago the pointer in the upper left sold for $50, and was a deal. The
tangle on the right consists of a battery pack with the laser LED driver circuit and two
laser LEDs. The small brass-enclosed one is a typical red LED laser, while the aluminum
one holds an infrared laser diode from an old laser printer.
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| Strobes |
| For a touch of the dramatic, integrate a strobe into your prop. I have yet to use
these in any costumes, but many times in Blasters, Phasers, rifles, and that same Dark
Trooper cannon. Others have added strobes to props such as wizard staffs and the like.
This would make for a bright surprise if combined with other lighting effects behind eyes
or concealed elsewhere on a costume. A strobe consists of a small xenon filled glass
tube, and a high voltage power supply that charges up a capacitor to several hundred
volts. A trigger transformer begins the process of ionizing the gas in the tube. Once
started, the resistance between the contacts in the tub drops, allowing the high voltage
in the capacitor to arc across the gap. The result is a blinding white flash as the xenon
gas lights up from the current passing through it. While fluorescent power supplies may
not create much more voltage than the strobe uses, it lacks the capacitor that stores the
electricity and releases it all at once. The difference is current. Fluorescent supplies
generate very low current, and while you can get a nasty zap from it, it is not likely to
do much more. But the capacitor discharge from a strobe is releasing hundreds of volts of
power all at once, enough to hurt very badly, burn, or cause other serious heath issues -
it might not kill you, but you will definitely not like it. Be very cautious when working
with any of the power sources mentioned here, especially strobes! |
Some strobes taken from disposable cameras. These use a single size AA battery to
charge the strobe. Their small size works well to incorporate into weapon props. Be very
careful when handling these - the capacitor can hold a powerful charge, long after the
battery has been removed.
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| Chemical light sticks |
| The only thing I have used chemical light sticks with was on the radio controlled base
for the energizer bunny in my Dark Trooper skit. I have herd of people using them in a
similar way as I used fluorescent lights in the Chernobog costume - as a backlight for
glowing eyes or some similar purpose. The advantage is that no special wiring is needed to
use these, but the disadvantage is that they last only for anywhere from 30 minutes to
several hours at full brightness. You also must plan on leaving these accessible to
replace them before each use. Chemical light sticks are flexible plastic filled with a
liquid. Inside the tube is another smaller glass tube filled with a different liquid.
Bending or flexing the plastic tube breaks the internal glass allowing the liquids to mix.
Once mixed, the liquids give of a bright glow, usually a yellow-green in color. Newer
colors include red, yellow, orange, blue, and white. Miniature light sticks are also
available - apparently some people insert these into translucent golf balls for playing in
the dark. |
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| Phosphorescent materials |
| So far I only use things like glow in the dark plastic string for costume accents. On
the Chernobog cape and bald mountain skirt, glowing plastic string (as seen to the right)
was used to make waterfalls off of the mountain. Although I have toyed with different
products, one approach is to use an ultraviolet light behind the plastic to create a
uniform glow. The effect is generally so dim, it can only be seen in low lighting or a
dark room. In the image to the right, several phosphorescent toys glow under ultraviolet
light. They continue to glow even after the light is removed, but dim rapidly. For a
costume or prop, these items would have to be constantly recharged to be seen.
The toys include small flying disks, glowing smiley face balls, and glow-in-the-dark
plastic "string". The blue glow at the top and bottom are the ultraviolet lights
used to take the picture. |
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