Hi,
I thought I had been on this board before talking about
Fiji, but I was confused between this board and Cruisers Log (same bbs
software, I guess). Just to introduce myself to those who don’t know me from other boards, like SSCA, Cruisers Log, CS-BB and others, I’m 1/3 of the directors of Bebi
Electronics, Ltd. in
Fiji. I’ve been a
live-aboard sailor since ’81, and cruising/working/living in a variety of SoPac islands since ’86. We are currently moored up in Savusavu, as we accepted a
contract to manage Waitui Marina (where our business office is) when my wife (and one of the directors) became 'in a
family way'. Gavin, my son was born in January, has 1500nm under his belt, and at the end of this year when our
contract runs out, we'll be moving back home to Fawn Harbour, where our manufacturing is.
Normally, I stick to Fiji, cruising, or
electronics in general, and I wouldn’t respond to a discussion about our products directly (advertising, not really appropriate to the spirit of the boards), but being slightly slandered (no need to panic, I’m an American by birth, not outlook: No one’s getting sued!
), I feel somewhat compelled to respond, hopefully including information that will be of general use in
purchasing LED
lighting products, in general, also.
Here goes:
In the early 1970’s, I purchased a set of Bose Speakers. Dr. Bose of MIT, the inventor, refused to ever publish any specs in lieu of getting into the specs ‘game’ (more later about this).
Bebi Electronics is currently using the Nichia NSPW5nnDS series of 5mm ‘lamp-type’ LEDs in its products.
Dr. Nakamura of Nichia is credited with being the inventor of the ‘ultra-bright white’ (in quotes, as in
lighting, the terms ‘ultra’, ‘bright’ and ‘white’ are as valid as they are in a soap powder advert), and continues to lead the field in the chemistry of the PN junction (think filament of a light bulb) and the reflector, which turns the ‘blue’ LED into a white one.
Unlike SSC (Seoul Semi-Conductor), who is embroiled in constant
legal battles with Nichia for ‘lifting’ its reflector technology, Phillips LumiLED took a different approach in the chemistry of its reflector phosphor, which saved it a lot of court battles, but also produces a slightly (slightly, mind you!), less ‘white’ device.
As long-term Nichia customers, we were using the ‘DS’ series device in our products prior to their official production release last November (2007). This is thus, far from an old technology in the actual LED dice.
Moving forward (and why the comments aren’t a complete slander), is that rather than using an SMT device with heat sinking, we have instead chosen to remain with the 5mm (T1-3/4) form, as opposed to switching to a device package, such as is
sold by Phillips, which relies heavily upon a heat sink technology to drive the junction at a higher
current without destroying either the PN junction, or the reflector coating.
There are many reasons why we have chosen the 5mm lamp approach, in spite of the technology advantages of the SMT case design of Phillips, the largest two of which are; first, the issue of waterproofing our product; second, our secondary business goals are to have the units assembled by hand, rather than robotically, so that they can be manufactured in the village of Bagasau.
Aside from the case differences, something else that needs be looked at is how we arrive at our specification numbers, as opposed to what others advertise (the specs ‘game’).
We advertise what the average lumens are, across the light cone specified, with the actual bin lots we
purchase, at the actual drive levels that we run the LEDs at. The idea here is to give the customer as realistic representation of what they are
buying as possible. Since a lot of our customers are converting from halogen or incandescent, I’ve tried my best to graphically illustrate the differences in the technologies (and other ‘stuff’) on our page
Bebi Electronics-What Our Marine RV & Off Grid LED Specifications Mean in an accessable way as I can, while still remaining technically accurate.
(This is going to get technical, sorry. If you aren’t interested, skip down to the paragraph beginning ‘Back to the Bose…’) Taking a look at the Phillips web site at what they advertise as being their ‘latest and greatest’, the Luxeon K2 with TFFC, and downloading their paper, DS16, take a look at diagram 19. What they rate in their advertising is the MAXIMUM output at the zero axis, not an average over the entire coverage section, as we do.
Further, you have the amount of light produced as opposed to the input
current. Again, relying on the same document, Figure 1, and column labeled ‘typical’ (which is what we base our own numbers on, not maximum), you’ll see 220lm/1.5a of drive current, or, stated another way, it produces 0.147 lm/1mA. If you were to apply (in the case of our Kalokalo light) 60mA, that would be 8.8 lm (as opposed to our 15) generated from their device for the same input current, but again, only at the maximum point, not the average!
As you can see from the above example, the total quantity of light emitted from an LED is a matter of how much current you drive it with, but the efficiency of the LED is remains based on the chemistry of the PN junction.
Since the object of the exercise is to reduce current
consumption and
cabin heat (where do you think the heat from the sink goes), what is the point?
In addition, LEDs will not cure bad backs, failing sex drive or flat feet. If you want a nice, warm, evenly and fully lit,
cabin, stay with (or move to) a CF. (LEDs day will come, however!) At 1.5a drive, an Alpinglo CF light does a great job of cabin lighting (we have no connection with Alpinglo, I just think they make a nice product)!
The advantages to the Phillips approach to an OEM are obvious to an OEM-if you can drive a
single device harder, as opposed to multiple devices, you can save a considerable amount of assembly costs, especially using SMT devices in a robotic
environment.
Another little ‘gotcha’ is the
concept of ‘binning’ by manufacturers of LED devices. What is often published is the performance of the highest rated ‘bin’ of a given device. (My opinion is that the manufacture of the ‘white’ LED is in its infancy, as the binning of devices is done after manufacture based on testing of the completed lot, not something ordered by the Production Control department. I cannot qualitatively substantiate my opinion). The specifications that small lots of LEDs are typically
sold as being are those of the highest bin sort, not the lowest or the mid-range.
Which devices an OEM receives is a function of what is ordered and what is allowed to be ordered; typically a range of bins is all that is allowed by the manufacturer.
In the case of Bebi Electronics specifications, we specify based on the bin range that we order, not what the maximum bin is within the device range: ~30% greater output than what we are actually using. Again, the emphasis is on accuracy and integrity, not ‘specsmanship’, however tempting it may be (and you’d have to look at our bottom line to understand the temptation!).
Back to the Bose Speakers: I eventually sold and replaced them first with JBL studio monitors, then later replaced them with a pair of ‘baby Maggies’ and a 36” Cerwin-Vega sub-woofer. (Pent-ultimately, I found I didn’t care for the sound of the Bose 901s. Ultimately, I found I didn’t even like living on land, sold the whole shooting match, used the proceeds for a down payment on my first
boat, and moved aboard it in ’81.)
Light, as is similar to sound, is truly a very, very personal thing, and no two people ever perceive light colour or intensity exactly the same. The CIE chart merely defines for comparison, it does not indicate what you see. Just to make the old farts feel worse, you loose roughly 50% of light energy sensitivity by age 50, between 50 and 60, another 50%! A
radio comparison (as cruisers you would be familiar with) would be if you saw at age 20 ‘S-9’, at 50 it would be ‘S-8’, and 60 ‘S-7’.
My suggestion is rather than converting all of your lamps at the same time to the same brand of device (including our own!), is to get down to a ‘short list’,
purchase one of each, and if you like it, continue the march with it.
No
single manufacturer can meet the expectations or desires of every persons ‘taste’ in both colour and intensity.
Thanks for wading thru all this crap, you’ve earned a gold star AND brownie button!