50 years! Lets hear it for the LED!
Discussion
Lets all give thanks to Prof Nick Holonyak Jr. for his discovery/invention of the LED! 
Without it, my ride home from work in the dark would be a worrysome affair - my route illuminated by a feeble filament bulb - perhaps powered by a 4.5 volt cycle battery with one spring terminal on the front, and another on the top.
Yes, remember those?? What? Not old enough?
You screwed down a plastic knob to turn them on, tensioned by a rusting coiled spring which creaked!
Eventually the lamp reflector separated from the lamp body/battery holder as it rusted through - quickly if you let the battery leak!
http://www.bbc.co.uk/news/technology-19886534
So there you have it - a device which is so versatile, I didn't know which topic title to post it under - road safety, or environment, hobbies or family health!
Not sure how much extra reaction time LEDs give over filament brake lamps though.... Prof, you're over egging it a bit!
Without it, my ride home from work in the dark would be a worrysome affair - my route illuminated by a feeble filament bulb - perhaps powered by a 4.5 volt cycle battery with one spring terminal on the front, and another on the top.
Yes, remember those?? What? Not old enough?
You screwed down a plastic knob to turn them on, tensioned by a rusting coiled spring which creaked!
Eventually the lamp reflector separated from the lamp body/battery holder as it rusted through - quickly if you let the battery leak!
http://www.bbc.co.uk/news/technology-19886534
So there you have it - a device which is so versatile, I didn't know which topic title to post it under - road safety, or environment, hobbies or family health!
Not sure how much extra reaction time LEDs give over filament brake lamps though.... Prof, you're over egging it a bit!
. I now wear one like this.I had a look at the LED LENSER X21 torch - and inadvertently pressed the switch as I turned it round to see how many LEDs were in the array - and blinded myself for 15 minutes!!
From my window I could put a circle of light on the cladding of the building across the street in daylight!
Morcambe Bay Search and Rescue Group use an X21, as well as P7s for individual members (I have one of those too!)
http://www.youtube.com/watch?v=CYUipzqfFkA
http://www.youtube.com/watch?v=KGqWNPHHtlU
Halfords charge £300 for this, but if you shop around you should get £225 or so.
From my window I could put a circle of light on the cladding of the building across the street in daylight!
Morcambe Bay Search and Rescue Group use an X21, as well as P7s for individual members (I have one of those too!)
http://www.youtube.com/watch?v=CYUipzqfFkA
http://www.youtube.com/watch?v=KGqWNPHHtlU
Halfords charge £300 for this, but if you shop around you should get £225 or so.
There's a thread in the bike forum (MTB lights) - a number of people are ordering CREE bike lights because they are simply incredible. Truly difficult to understand the science behind something that can create so much light from such a "point" source.
I'm guessing the OP is talking about his original bike light which may have looked similar to the one fixed to the front of my Dad's bike in the late 1950s:
The pace of life was slower but even so, I'm amazed that gave out any useful light for any useful length of time. I had plastic equivalents with 2x D-cells back in the 1970s and they were pretty grim.
I'm guessing the OP is talking about his original bike light which may have looked similar to the one fixed to the front of my Dad's bike in the late 1950s:
The pace of life was slower but even so, I'm amazed that gave out any useful light for any useful length of time. I had plastic equivalents with 2x D-cells back in the 1970s and they were pretty grim.
Mars said:
There's a thread in the bike forum (MTB lights) - a number of people are ordering CREE bike lights because they are simply incredible. Truly difficult to understand the science behind something that can create so much light from such a "point" source.
I recently picked up an Ultrafire CREE torch from ebay, £20, 1000 lumens and two rechargable batteries. Maybe not quite as good as the led lenser, I don't know, but only a 10th of the price and frankly incredible. Stupid amounts of light.My bicycle (1970s) had a 'dynohub' and it worked perfectly.
I'm not much in favour of the flashing Christmas tree lights on bikes now - when driving I find the flashing and general dancing about distracting and a small 'point' light source is not so easy to see/calculate distance/speed after dark.
But of LEDs in general, yes, great things.
I'm not much in favour of the flashing Christmas tree lights on bikes now - when driving I find the flashing and general dancing about distracting and a small 'point' light source is not so easy to see/calculate distance/speed after dark.
But of LEDs in general, yes, great things.
Mars said:
There's a thread in the bike forum (MTB lights) - a number of people are ordering CREE bike lights because they are simply incredible. Truly difficult to understand the science behind something that can create so much light from such a "point" source.
I'm guessing the OP is talking about his original bike light which may have looked similar to the one fixed to the front of my Dad's bike in the late 1950s:
The pace of life was slower but even so, I'm amazed that gave out any useful light for any useful length of time. I had plastic equivalents with 2x D-cells back in the 1970s and they were pretty grim.
That's the one - although it appears to have the simple click switch, rather than the screw down affair. As to light output... my carbide lamp gives out more!I'm guessing the OP is talking about his original bike light which may have looked similar to the one fixed to the front of my Dad's bike in the late 1950s:
The pace of life was slower but even so, I'm amazed that gave out any useful light for any useful length of time. I had plastic equivalents with 2x D-cells back in the 1970s and they were pretty grim.
Ebay is great for decent lights - and the more you have the better these days - my route is rural with no streetlights!
madala said:
I find some of the LED lights on bikes and on the emergency vehicles much too bright....I have to shield my eyes or I loose my night vision.
I try to adjust mine so as not to glare, but have one on my helmet which I can aim high straight at drivers who don't dip their lights for me! It is handy when turning into junctions too, as the beam goes wherever I look!
Watchman said:
Yup. Even has the classic rust at the bottom due to battery leakage.Mill Wheel said:
I try to adjust mine so as not to glare, but have one on my helmet which I can aim high straight at drivers who don't dip their lights for me!
It is handy when turning into junctions too, as the beam goes wherever I look!
I've just fitted a Magicshine knock-off to my lid to see how it improves night riding. I also have 2 more on my handlebars. I'm going for the overkill look but I don't ride on the roads at all.It is handy when turning into junctions too, as the beam goes wherever I look!
Audi a full LED unit with headlights/indicators and DRls on the new S3.
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