|
C-7 Home Page |
||||||||||||||||||||||||||
|
Rigel Systems "Skylite mini" Red/White LED Compact Flashlight
The Skylite are a unique series of handheld flashlights ideally suited to the needs of astronomers, or anyone who must work in low light while preserving their night (scotopic) vision. The Skylite flashlights are readily distinguished because it can do double duty as a conventional white light flashlight; this makes it an especially good choice for those who travel far from home to remote locations and carry a Skylite as a primary or backup conventional flashlight.
Left: Rigel
When Rigel developed the original
Regardless of the competitors merits the cloning began to impact Rigel sales, and so Rigel responded by developing the dual Red and White LED Skylite. It was the Skylite which become the compact flashlight of choice. Then in the Fall of 2003, Rigel introduced their next generation light - the Skylite II.
December 2005 marked the introduction of the "Skylight mini", a more compact dual Red and White LED more closely resembling the original Skylite, but in a notably more compact arrangement. The reasoning for this had to do in part with the fact that the water resistant Skylite II is at 5-1/8 inches (130mm) just a bit too long to fit into spaces of many fishing tackle and utility box compartments. The Skylite mini is 3-2/3 inches (93mm) in length overall - keep in mind the 9 volt battery alone accounts for 48mm of length! The Skylight mini differs from the Skylite II in two basic ways:
* If Skylite mini becomes immersed in fresh water or if dew fogs the interior, then simply turn it off, disassemble it (disconnecting the battery), and set the parts aside to dry in a warm room before reassembly. If immersed in salt water then add the step of rinsing the electronics in fresh water, then pat dry and set the parts aside in a warm dry room for a day or so before reassembly.
While conceived for the astronomy community, Rigel Skylites are useful by anyone who may have to work in the dark and they have found their way into applications by the military, aviation, theatre stage workers communities and more. Hikers finds these to be an most convenient aid that is less likely to disturb wildlife at night. Most employees of Company Seven keep a Skylight close at hand in the home night stand, in our automobiles, in a tool box, etc. These are a utilitarian and affordable gift idea.
Why Red?
Daylight as we observe it is made up of red, green and blue light in that portion of the spectrum which the human eye can detect, this region is known as the visible spectrum. This occupies wavelengths from approximately the deep violet in the shorter wavelengths just below 400 nanometers (nm) up to the longer wavelengths of the deep red at about 700 nm. The human eye evolved to help us survive in a day lit world dominated by the green of vegetation, as such it has developed a photopic (light-adapted) sensitivity that spans from about 400 nm to 700nm, peaking at about 555 nm. Since the eye is so sensitive here this is why some emergency vehicles are painted "slime lime" so that they are very obvious for example. And our scotopic (dark-adapted) sensitivity ranges from 400 nm up to 620 nm losing some red efficiency peaking at 510 nm. The human eye responds to low light levels by dilating (opening) the Iris diaphragm to permit a greater area of cones and rods in the Fovea of the eye to become stimulated. If the eye is exposed to common white light, then the Iris will constrict thereby reducing the eye's sensitivity to seeing faint objects. To see how this works, walk into a room and turn off the lights - notice how over time you will be able to see more and more fine details in the dark room as your eye adapts to this. Scotopic vision has been understood for some time, this is why military vessels switch to red light when operating at night. And this is why astronomers avoid white light sources when trying to attain and preserve their night vision.
Above: Visible portion of the electromagnetic spectrum with bordering regions (20,129 bytes).
As with many other night time use flashlights, the Skylight can provide a red light. However, while many other flashlights employ incandescent bulbs with a red filter or painted lens to dim the light and provide the dark red color, the Skylight employs two red Light Emitting Diodes (LED's) arranged side by side. The Skylight incorporates a rotary dial on-off switch with variable intensity potentiometer to permit the user to vary the brightness of the LED's. The circuitry regulates the power so that as a battery voltage drops the illumination will not fade. The LED's are durable and almost never burn out, and their uniform brightness can be lowered across a wider degree than most incandescent sources. Furthermore, since the Skylight has two red LED's side by side in a rectangular housing, then the medium flood light pattern is more uniform and better suited to the study of charts and common documents.
SkyLight Flashlight Common Features:
Skylite Mini Features
Battery Changing Instructions
| |||||||||||||||||||||||||
