Posts Tagged ‘LED’

Inspired by high speed photography

A conversation piece inspired by high speed photography

My involvement in lighting was born from a graphic arts and photography background, so imagery remains a core interest of mine. Design 9 was inspired by a particular image of a rifle scope being shot through by another rifle, creating an eruption of glass that caught the light. We’ll get to the reason this was being photographed, and why in a moment. First, what intrigued me was how high speed photography today catches moments in time that are beyond human comprehension. We are blind to most wavelengths of energy, we know that. But, what we seldom recognize is that the slowness of our visual processor is such that we comprehend only a fraction of what is actually happening around us. Time lapse and high speed images catch a fraction more of this missing perception. Time laps images capturing the blooming of flowers, showing that these organisms live in a slow motion universe outside our comprehension. High speed photography shows us the micro-moments that occur while our feeble brains process sampling of bits.

Image out-take of the high speed photography caught by the Mythbusters

Image out-take of the high speed photography caught by the Mythbusters shows the spray of glass from the bullet entering the scope, which inspired me to attempt to create a static object that produced a similar visual impact, representing a successful result.

High speed video images of bullets blowing through fruit, and in this case a rifle scope, capture the impact and movement of an object weighing a few grams, traveling at 2000 feet per second, revealing the release of the energy this creates.

Now to the specifics. D9 is a conversation piece, meaning it is designed specifically to start or incite a conversation, even an argument. The visual effect I was attempting to capture was This particular image from an episode of the Mythbusters (History Channel property). They were testing whether the legend of Carlos Hathcock shooting a sniper through his scope in a legendary incident in Vietnam, was mechanically possible. In this, they placed several scopes some distance down range and shot rifle rounds through them to either deem it plausible or busted.

Conversation Note 1: The test was flawed in that it did not test period correct, North Vietnamese  optics. First, the optics of that day were not variable, thus were far simpler than the compound optics tested in the episode. I’ve dismantled several scopes over the years, and can confirm that the internals of modern scopes would be impossible to penetrate. In fact, the scope used in this design took a great deal of effort to “disassemble” with a steel rod and hammer, as the center section (area under the turrets) is very dense in compound lens segments of very small diameter. Fixed, simpler scopes do not include this denseness. Further, the tests did not represent the actual energy of impact accurately, as the distance of the shot was less than 50 yards, let alone 500.

The optics of a bullet passing through a scope are compelling, and invisible to us without high speed photography.

The optics of a bullet passing through a scope are compelling, and invisible to us without high speed photography.

Optics of Discussion. In thinking about this design, I was captured by the various “optics” involved. The optic of the angles and geometry involved in the shot, the optics of the and within the scope being shot. the optics of the shooters scope, the optical challenge of shooting through a tube that is 1″ in diameter, with a thin shell presenting an entry target of 1.5″, from a distance of 500 yards (a little more than a quarter mile), the optic imagery of the bullet passing through the glass, and the unavoidable optic of the repercussions of such an accomplishment. I was also captured by the reaction of the glass, and the release of energy in both the entry and exit directions (shown in tests by others) when the shot is made. Its all very intriguing, which is what makes it such a compelling story / legend.

Any deviation from a straight through shot would likely have resulted in less than a straight through result.

Any deviation from a straight through shot would likely have resulted in less than a straight through result.

Conversation Note 2: The scope Hatcock used was an 8 power Unertal and the distance the shot was taken from was 500 yards. The claim is that he saw a glint of light from his target, which he used as a point of aim. The optical field of view of an 8 power scope at 500 yards is around 75 feet. Thst  means he was able to recognize and place a target that was 1/600th the field of view, smaller than the width of the cross-hair wires inside the scope of the day. While not impossible, this is on the very extreme edge of it.

Conversation Note 3: The glint from the targets scope indicates the sun was behind Hathcock, and that his target was aiming at him directly into the sun. With a field of view of the same 75 feet, he was not only fighting the glare from the sun through optics with marginal clarity, he was seeing Hathcock in the shadows at the same 500 yards? This seems the most unlikely aspect of this story.

Conversation Note 4: At 500 yards, for the bullet to travel through the scope tube, the angle would have to be essentially perfectly in line with the scope axis, as any deviation from that angle would result in deflection defeating the the result. That means zero wind drift effect, and zero angle of inclination between the shooter and the target. This seems optically possible, and practically on the verge of impossible.

Conversation Note 5: The bullet would need to not only travel the distance of 500 yards but still have enough energy to drive through the scope itself. At that distance, a 175 grain 308  bullet would still be carrying an energy of 1167 ft. lbs of energy, about the same as a 22 LR bullet at point blank range. This seems enough energy to drive through the scope glass. Whether or not there would be enough energy or enough of the bullet itself intact after blasting through the glass is another story.  It is possible that the lower energy state is what kept the bullet from exploding when it struck the scope, which renders any tests done with higher energy states for verification totally invalid.

That all said, Hathcock was one of the best shooters of the time, decorated many times, and recognized for his contributions. Nothing here is intended to defame that. His credibility is what makes this whole story so intriguing, as he had no reason to fabricate such a story at all. I have seen some truly jaw dropping shots taken by marksman in my own 40+ years of shooting to know that there are people who know how to place shots with precision beyond human comprehension, high speed images or not. The shot is not impossible. The bullet, once loosed, was going to travel through a spot in space down range equal to its physical diameter of .308″. That could have, indeed, been within the diameter of the objective bell opening of a scope.

My goal was not to prove or disprove the legend. My goal was to create a static object that presented the visual, or optics, of the composite moments of the bullet traveling the last 24″, and the spray of glass that would have resulted in both directions. The glass spray was created by printing two structures on the SLA machine in transparent material, then coating those with clear urethane, which was then dusted with shattered glass. Internal to the scope are 2 LEDs aimed outward. The top turret cover is a dimmer knob, while the section of rifle below, printed on the FDA machine (sanded and painted) houses the driver and a military style on-off push-button switch to cap the whole design aesthetic.

 

 

Edit May1

As demonstrated in D1 of this series, LEDs and solid-state technology are changing more than general illumination. Other instances of applying near UV  LEDs with emission to cure light-cure resin composites. We have applied this to replace Metal Halide light sources that require 20 minutes to start-up, and are skin frying monsters. LED cure lights are also more predictable and focus-able than natural light, and can be applied indoors, and less bulky and more powerful than fragile fluorescent cure systems. LED sourced cure lights are now used in printing, dentistry, and commercial production of resin-based composites. We are also applying this on small and large scale applications from the very small (like D1 SLA curing) to larger scale units for curing large objects, like fiberglass repair of boat hulls, custom automotive body panels, and low odor repair of fiberglass bathtubs and shower floors. The use of LEDs produces instant-on high intense light, with much less power,  significantly less heat in the lighted pattern, less exposure to hot surfaces, and contain none of the damaging ultraviolet light that does nothing to enhance curing, but is harmful for operators. The use of UV initiated resins offer the advantage of extended shelf life as there is no catalyzed resin to harden in the container and less odor for use indoors. An update with  new images and details will be posted here when available.

The retro black egg - origins unknown.

The retro black egg

I found this little light on ebay at a lunch money price, so couldn’t resist. It started life as a Hamilton Industries (Chicago) lamp model 60, made in Japan in the early 1960’s.   It used a 12V magnetic transformer and a resister to provide a dual level light control of its 20W signal lamp. The amount of light it put out was barely visible in the presence of any ambient light. Meanwhile, I had a cute little key-chain wireless remote controller for less than $14 from LED Supply that delivers PWM dimming and on-off control of 12VDC LED loads. I stripped the guts out of their kit and put them inside the base of the fixture. The little lighting head was about the right size for a 12V MR16 lamp, so rather than re-invent that wheel, I just retrofitted the head to take a bi-pin socket and planned to use a retrofit MR16 lamp to deliver the light I wanted. That ended up more of an issue than I expected. First, after testing of all the LED MR’s I had around, only one brand would operate and dim effectively when run on DC power. The rest were poor dimming on AC power, but on DC they were miserable. On the LED Supply remote dimming module, they were useless. The lamp I ended up with was a Philips Enduraled product, and it will dim down to around 10%.

The remote control acts as a panel control when nested in the base, and as a remote control with cute antenna when separated.

The remote control acts as a panel control when nested in the base, and as a remote control with cute antenna when separated.

The remote control is a bit of fun, as it has an antenna that works well with the antenna arm on the fixture, so they seemed a great match. I printed a holder for the face of the power supply (now control) enclosure at the base of the fixture to hold the remote, which makes it a simple panel controller when the remote feature is not needed. When the light is used to wash a wall or light art or some other function besides a desk lamp, the remote can be removed and control the fixture from across the room. The power supply is a simple 12VDC wall wart, while the base houses only the remote control electronics now.

The base now incorporates the remote in a recessed compartment.

The base now incorporates the remote in a recessed compartment.

The base looked in need of a bit of dressing up, so I printed a retro-turbo trim ring to surround the remote control mount on the SLA printer and painted it with VHT fake chrome to give it a sand-cast aluminum look. I also printed the same part on the FDM printer for comparison. I’m throwing in two images of the raw prints to show the difference in surface quality one gets between these machines. Obviously, for parts that include details that will be hard to sand and fill, the SLA process is superior. For parts that need to be strong and can be easily finished, the FDM is the go-to tool.

The lighting head uses an LED MR16 lamp for its optic and driver components

The lighting head uses an LED MR16 lamp for its optic and driver components

So, this little weak black egg ebay find has been transformed from a barely functional desk lamp novelty, to a bright, useful, remote controllable, dimmable, black egg turbo trimmed LED light novelty. I’m a fan of the 50’s and 60’s design aesthetic, so this one felt right and was fun to put together.

The turbo fins look very rocket-man when the egg is closed up

The turbo fins look very rocket-man when the egg is closed up

 

 

 

 

 

 

 

The remote facilitates using the light as a wall accent, or ambient uplight, controlled from elsewhere in the room

The remote facilitates using the light as a wall accent, or ambient uplight, controlled from elsewhere in the room

With the remote out, the light can remain on, lighting the turbo louver as a night light

With the remote out, the light can remain on, lighting the turbo louver as a night light

The ebay purchase

The ebay purchase

The cord was ugly and the closed appearance rather out of alignment and boring

The cord was ugly and the closed appearance rather out of alignment and boring

While FDM 3D printed parts (top_ are strong and easily finished, in fineer detail work, they lack fidelity and smoothness. The SLA (bottom) part is much smoother, requiring less finish work, but are less durable. In this case, the FDM is printed at its finest setting, the SLA at its coursest, so the contrast here is greater when the SLA is pressed to maximize reolution. Both took 2.5 hours to print.

While FDM 3D printed parts (top_ are strong and easily finished, in fineer detail work, they lack fidelity and smoothness. The SLA (bottom) part is much smoother, requiring less finish work, but are less durable. In this case, the FDM is printed at its finest setting, the SLA at its coursest, so the contrast here is greater when the SLA is pressed to maximize reolution. Both took 2.5 hours to print.

 

Overall height is 19". The base is a salvage item from Goowill.

Overall height is 19″. The base is a salvage item from Goodwill.

I am a task lighting fanatic. I use them everywhere, so am always looking for something new to add to my collection. In this installment, I am addressing the need for a light that is compact, delivers intense light (1,200+ Fc) with no glare or brightness, and high color accuracy. The application is pretty straightforward, from soldering station use where a magnifying glass is used, to fine detail work inside or on the outside of models.  For good measure, I also wanted it to aim at the wall as a photo fill light, or straight up as am ambient fill light, and have a dimmer to allow me to set whatever level I want for the application in hand at the moment.

The wiring and components are left skeletal.

The wiring and components are left skeletal.

With all the practical specifications set out, I decided to let this design be expressive of the gadgetry involved. Let it all hang out. I also decided to incorporate the new Bridgelux Vero LED with its integrated Molex connector, and a Nuventix cooler, just to amp up the tech factor.  This is where things got interesting. The Bridgelux array operates at 33.7V (500mA). The Nuventix cooler at 12V. I am powering the whole thing with a 24VDC wall wart power supply. That meant I needed to employ a boost driver for the LED and a buck (24VDC to 12VDC) power converter for the Nuventix cooler. I used Recom components to attain this, and used a cut up experimenters printed circuit board to connect these two to the power supply, the cooler, the LED and the dimmer control. That’s a lot of wires to find a path for, so I decided to leave them to roam free, let everyone see the components as well.

The lever on the left of the head is the on-off slide switch.

The lever on the left of the head is the on-off slide switch.

This is a style of design I personally enjoy, and have been doing since the 1980’s, where we made little 12V lamps with fiber optics, MR16s, halogen burners, or automotive headlamps, often suspended from structures made of building wire. In this case, the stand I found at a Goodwill. It was a table lamp, whose shade was gone, and socket was cracked. I liked the cast iron base and single post stand, so nabbed it for a dollar and tossed it in the pile with my other finds, waiting this moment to be put to service.

The wiring at the driver and power supply are exposed as well as the mess of wires leading into and out.

The wiring at the driver and power supply are exposed as well as the mess of wires leading into and out.

If you look at the head, the switch is a sliding action, on the left side of the head. Pull it forward to turn it on, push it back to shut it off. A hole in the side of the housing allows you to see the action inside. No, there is no reason for this, other than it seemed more appropriate than an off-shelf toggle or twist switch.

The light on the task surface is at 1,425 Fc, the LED is 3000K, 97CRI.

The head can pivot 180 degrees from down to straight up.

The head can pivot 180 degrees from down to straight up.

The 3D printed shade was an interesting experiment. Can also print in red or blue plastic.

The 3D printed shade was an interesting experiment. Can also print in red or blue plastic.

In playing with the Philips Hue system, we found wireless controls to be an effective means for solving lighting issues we have around the house. One area is the main stair. While the overhead track lighting system does a fair job lighting the art on the walls, it is a bit much when all we want to do is have a little light to navigate by. I also wanted to have the light turn on and off automatically, to provide a level of ease, and to get rid of the issue of forgetting to turn off the stair lighting on the way to bed.

The view from the floor below.

The view from the floor below.

Applying a wireless light, programmed to turn on-off and dim is a great addition, and an opportunity to create a new fixture while I was at it. The added feature of color changing to suit the lighting mode is a serious bonus and a lot of fun. Since the light from the stair itself is visible through a window facing the street, the effect of color here creates an interesting effect from outside as well. This design explores printing translucent materials for creating the shades, in addition to printing the rest of the fixture from ABS overall. The design itself is a bit freestyle, mixing a little Art Deco with Hi-Tech, influenced a little by American Indian… The light source is the Philips Hue A-style lamp, which has been modified through the addition of a bottom shade closure to hide the light source from below. The challenge with this design was to hide any direct view of the light itself, as at night the brightness was too great. I would like to have eliminated the cord connection, but tearing the stair railing apart to drill a wire channel through it was not on the agenda.

The 3D printing process (FDM) adds texture to the shade material.

The 3D printing process (FDM) adds texture to the shade material.

Now, we let the light run its program, and don’t have to remember to turn things off when retiring. We can also use the light to create a visual presence when we are out and away by setting different on-off times, color effects, etc… which from the outside, looks like things are moving and changing inside.

Deco-Tech is the best I can come up with to describe the design vocabulary used. It's really just freestyle.

Deco-Tech is the best I can come up with to describe the design vocabulary used. It’s really just freestyle.

Interesting note about color in this application. The very low blue light level makes seeing things in the stair when no other light is present very easy, so the level can be set low. Yet, this setting is easily ignored, and does not feel like a light on in the hall. I’m not concerned about the blue color interfering with sleep or melatonin suppression in this application, simply because the total energy we are talking about is so low (<.1 Fc).

Unfortunately, digital cameras have a hard time dealing with saturated colors, so this photo fails top show what this actually looks like (blue lighted portion). You can get the idea though, and having it cycle slowly through different shades is very pleasing.

Unfortunately, digital cameras have a hard time dealing with saturated colors, so this photo fails top show what this actually looks like (blue lighted portion). You can get the idea though, and having it cycle slowly through different shades is very pleasing.

warm

I was hoping to get a better image of this with the setting at 2200K and some saturated colors. Unfortunately the camera is fighting me, so I’ll just leave these with you to suggest how the fixture looks in other than white settings.

 

D2-img-4

D2 Front View

This weeks project is a concept model exploring an organic form of twisted and tapering ellipses. The height is 24″, and it measures roughly 3 1/2″ x 2 3/4″ at its base. The design is intentionally simple, utilizing a single LED strip concealed behind a valence to one edge. Total power at full brightness is 5 watts, and output is roughly 400 lumens total. The interior is covered with White Optic material to create a diffuse soft edged luminance from within. There is a simple stem dimmer control at the base circuited in series to the light strip, and a two position switch to the side providing full-on / off / dim settings. This model is powered by a wall-wart 24VDC power supply.

This was printed on a 3D printer, sanded smooth and painted matte white. In a production version casting the body in ceramic with a matte glaze would render a more finished end product. Low power LEDs don’t require much thermal management, can be circuited with on-board micro IC current control driver, creating a very simple to assemble and economic end product. Even in this plastic concept model form, the costs of the entire assembly were under $200, with the power supply.

D2-Img1

D2 3/4 View

D2 View 2

D2 View 2

D2 Back

D2 Back

D2 Top

D2 Top

D2 Base

D2 Base

 

The Purple Light ‘UV’ Cure Cube

The Cure Cube is used for curing SLA 3D Prints created on the Form Labs 1+ printer. Exposing SLA prints to 405nm "UV" light increases strength and creates a harder surface for final finishing.

The Cure Cube is used for curing SLA 3D Prints created on the Form Labs 1+ printer. Exposing SLA prints to 405nm “UV” light increases strength and creates a harder surface for final finishing.

While not particularly visible to everyone in the SSL universe, over the past few years one area of interest in LED product development for me has been in use of 405nm LED light sources to cure various plastics materials. The advantages are lower power requirements and reduced overall heat in the cure zone over conventional fluorescent or HID light sources. This has been of particular interest in curing fiberglass resins manufactured by Sunrez. The typical demand is for between 200 and 1,000 µW/CM² at 400-405nm wavelength. The use of LEDs allows us to generate exactly that without the waste of visible light, and longer wavelength power the resins are not reacting to. In one project, we were able to replace a 1,500W HID light source with a 120W LED light system that produced faster cure times with less than 10% of the total power, and virtually no heat added to the heat generated by the resin’s exothermic reaction to the curing initiator. Since then, we’ve built 405nm light cure fixtures ranging from 1,200W to 25W.

In this case, I needed to cure 3D prints we generate on a Form Labs 1+ 3D SLA printer, and do so in an office environment without exposing other materials and occupants to UVA light output. The material used in the print process is acrylic based, with chemistry that is photo-reactive to 405nm. The actual prints are made using a UV laser source. When the part is removed from the printer it is washed in alcohol (91% IPA), rested for a few hours to dry the alcohol off, then placed in this cure cube for an hour or more, depending on the thickness of the final component. The end result is a hard first surface for finish sanding or painting, if necessary, and a more rigid part as a whole (less flexible).

The cube is simple, with vent reliefs top and bottom to encourage ariflow. The flush switch on the top cover was created using 3D printing processes for the slider and body, as well as top and bottom cover.

The cube is simple, with vent reliefs top and bottom to encourage ariflow. The flush switch on the top cover was created using 3D printing processes for the slider and body, as well as top and bottom cover.

The cube utilizes a simple aluminum housing, with FDM 3D printed top and bottom covers. The top cover houses a single Recom 500mA driver, slide switch and wiring terminal block on a Tasca LED driver circuit board.

5mm 450nm LEDs with a FWHM distribution of 60º, 25 per side and top (125 total), operating at 20mA each, mounted to custom circuit boards sourced at Express PCB. Each board connects the LEDs in parallel, while the boards are connected in series, resulting in a 500mA, 15.4V circuit, totaling 7.7W. The boards and internal exposed surfaces inside the box were then covered with White Optics 98 matte material to increase total light energy and diffuse The light energy at 405nm is roughly 600 µW/CM².

The bottom surface includes a glass plate where the product sits in order to make any possible stickiness of a part from adhering to the White Optic material below.

The interior of the cube is covered with White Optics 98 material for optimizing light energy re-cycling.

The interior of the cube is covered with White Optics 98 material for optimizing light energy re-cycling.

The housing was powder coated matte black polyester to make clean up easy and the box look nice. The overall interior dimensions of the box are 1″ larger than the total build volume capacity of the printer itself (5 x 5 x 6.5), as any over-sizing is unnecessary. This produces an optimal match between the location of the LED sources and any part the printer can produce.

The Cube is powered by a remote plug mounted 24VDC power converter.

The operation of the box is simple enough. The box is lifted up, the part is set on the base, the box is set over the part, and the light is turned on by sliding the switch to the on position.

Simple and compact is the order of desktop manufacturing, and this fits that model perfectly.

A look into the box lighted up and ready to accept parts.

A look into the box lighted up and ready to accept parts.

Testing so far has shown the cube can cure raw resin from liquid to fully hardened in less than an hour, and strengthens prints in that time or less. The heat generated from this arrangement is so small, there is no chance of any part being warped or affected by the process, other than the desired results of becoming stronger.

For parts to be left unfinished, that are desired to be used over extended periods, we coat the finished parts in either acrylic or polyurethane UV inhibiting clear coat, gloss or matte. This stops ambient room light or daylight exposure from making the parts brittle over time. I am building a second copy of this cube for completing extended testing of samples of the materials we are using to verify clear coat effectiveness, behavior of the print material over long exposure periods, and the behavior of these low cost LEDs over time. A commercial version of this cube could be made using more robust LEDs, but the costs would be significantly higher as well. In the current configuration, the LEDs only cost $0.60 each, so should they last a couple of years in use, replacement of the populated boards is a simple task, while the cost of higher power LEDs would have increased the cost of the entire end-product by as much as three times.

There is also an additional version of this same approach in using Red/Blue light sources for use in plant seedling starts. We’ve found tests with common rye and barley grasses, the time from germination to hearty growth ready for planting is accelerated significantly. Using an enclosure like this allows the plants to be exposed to intense light for extended periods of time (18 hours or more) without polluting the surrounding environment with the ugly light, just as the enclosed cube protects room occupants from exposure the the UVA light. In either case, the cube can be used in any room environment comfortably and safely.

So this gets us off the ground and is D1 of 52 in the series. As I’ve noted at the start, this is an exercise in making progress, and putting SSL to work. This is not a particularly exciting product in and of itself, but it is one that will be used regularly, which more than makes up for its lack of marketing sizzle for the masses – at least in my book.

 

2015 is the International Year of Light and Light-based Technologies – a United Nations observance to raise awareness of the achievements of light science and its applications, and its importance to humankind. 

Edited 12/10/2015:

The concept of pursuing another round of 52 designs in 52 weeks was the original intent for this series. However, the time involved was not available, nor were we able to rationalize the costs involved. The work of the 52/52 2010 was a significant effort, that never truly delivered an ROI, either directly or indirectly. It was a lot of fun and reflected my exploration of SSL technology on a fast track. I’d hoped to attract others in playing along this time around. This never materialized. Faced with going it solo again, I came to the realization I just couldn’t get it done, so abandoned the project. It is a serious disapointment, but did free me the time to refocus on our business and move us into a larger and more productive state and facility, so not all was lost. The original 52/52 designation for the projects has been re-titled YOL, for the Year of Light. Yes, it is a bit of revisionist history, but its my blog and I have that right.. literally and figuratively.

With that in mind, I am still sharing projects being worked on within Lumenique that are exploratory, experimental, or customer project related (when we are allowed).

In 2010, we explored everything from steam punk to toys and practical tools. 2015 will be more of the same with a 3D twist.

In 2010, we explored everything from steam punk to toys and practical tools. 2015 will be more of the same with a 3D twist.

I combine work with solid-state light sources with another emerging and revolutionary technology we started working with in 2010 – 3D printing technologies. I now have (3) such printers on hand, including a commercial FDM printer, a desktop FFM printer, and a desktop SLA printer. With these, we can now make translucent and transparent prints, including simple optics, flexible parts, and smaller, highly detailed components and mold patterns for casting in metal and urethane. I’m anxious to put these to work in creating interesting final forms. I’ll also be firing up the glass kiln a few times, and hammering out a few pieces in the blacksmith shop to keep things interesting.

In the next few days, I will be posting my first entry to start the ball rolling with something for my shop, that others in the 3D print business may find useful.

That all said, I hope that 2015 has been a great year for everyone!

 

My first LED fixture - 2004-2006

My first LED fixture – 2004-2006

This is my last bit of housecleaning from blogs being shut down, for the archives. KLW

This fixture is my very first LED light. It started life to be a halogen fixture in 2004, that sat on a workbench waiting completion. The first head got so hot from the 50W 12V light source, it was dangerous, so it sat as I decided what to do with it.

In 2005, as LEDs became viable for lighting, I pondered using them to replace the halogen source, but they delivered so little light, the end product was useless as a desk lamp, so it sat some more. One idea was to insert a Lamina BL3000 LED into the head, but the driver was huge, the light output too little, and the heat still an issue.

Then, in early 2006, while at Visa Lighting, Don Brandt (an engineer working with me at Visa, formerly from Emteq, now working at Cree I believe) were talking through ways of applying the latest mid-power LEDs using a simple PCB. We decided to give it a shot and built a board populated by a vendor with 8 Nichia LEDs. The inspiration struck to power these LEDs with two Xitanium drivers, which at the time were un-potted prototypes, so cutting them out of their housing to be installed in clear tubes to show their interiors off was easy enough. Two push-button switches activated the drivers for a high-low effect, and a heat sink was made up of a machined aluminum block installed in the head where the original halogen lamp and reflector once lived. More details and images of this can be found on the Lumenique archives for the Ratchet fixture.

The fixture itself is made of welded steel structure with a brass head and fiberglass tension springs. The head can be raised an lowered with a ratcheting action, staying level at any height. In the end, I left this fixture with the owner of the Oldenburg Group (owner of Visa Lighting) as a parting gift as I moved on to focus on Lumenique and SSL exclusively.

There are many subjects in lighting, specifically in the universe of solid-state lighting, that need to be actively discussed and openly debated. Issues such as qualitative issues (color, color accuracy, glare, brightness, illuminance levels, etc..) over quantitative (lumens per watt), or the discussion of blue light content, or scotopic v. photopic, or supplier issues, or even the problems of being a small fish in a pond filled with big bloated corporate fish and a governmental agency who believes itself now a lighting expert… These all require active dialog to be resolved and grow understanding.  Too many times, the discussion of important topics are held in little rooms, hidden from view, with conclusions drawn, recommendations and regulations written – to be handed down like tablets from the mount, for us all to simply step in line and accept as fact. We have far too many instances of white paper writing scientists issuing their narrowly focused findings through their myopic peer groups, to be used as swords and weapons against the unwashed and unknowing masses. I find the creeping movement of lighting away from its roots as a human experience enhancing art-form into the hands of marketing zealots, narrow minded PhD’s working in their corporate labs, and federal or state agencies with agendas to follow outside our need to know… well, disheartening and disgusting. (more…)