Lamps trap previously wasted IR radiation to increase efficiency

[eppur_se_muova]

OK, this is kind of old ... 2001 ... but I hadn't heard about this. I had thought of similar things myself but this is the first time I've seen anyone apply this idea.

Halogen Infrared Reflective Bulbs - Harison Toshiba Lighting Corp - Brief Article
Automotive Industries, Feb, 2001

Harison Toshiba Lighting Corp. of Japan introduces Halogen Infrared Reflective (HIR) coated bulbs for forward lighting in automobiles and trucks. The HIR-2 low beam is a 55 watt bulb that produces 1,875 lumens output. The HIR-1 high beam is a 65 watt bulb that produces 2,500 lumens. Each bulb is has a 25+ JR exterior coating.

http://findarticles.com/p/articles/mi_m3012/is_2_181/ai_70935259

HIR lamp has an advanced optic interference multilayer film vapor-deposited many times, which blocks IR (Infrared Radiation) in the glass envelope and allows visible light to go through the film.

When generated lights at the filament coil reaches this multilayer film, its infrared radiation can be blocked at "advanced optic interference multilayer film," and reheat the filament coil.

The glass envelope is formed in anomalistic rounded shape in order to efficiently take Infrared radiation back to the filament coil.

By reheating the filament coil with IR discarded for visible auto-lighting purpose, these IR-reflective films are more than double the brightness while still maintaining its wattage.

http://www.harison.co.jp/pro/head/index_e.html

11. What is special about HIR lamps?

HIR stands for Halogen-IR. An IR (infrared) coating is placed on the filament tube of some of our halogen lamps. This multiple layer coating not only absorbs UV but also re-directs IR (heat) back onto the filament. By re-directing the IR back to the filament, the lamp produces more light for the same amount of energy and the amount of heat generated by the lamp is reduced when compared to standard Halogen products. Therefore HIR saves money by:

* Lowering UV emissions
* Reducing energy costs
* Lessening A/C loads
* Improving preservation of perishable displays

http://www.gelighting.com/na/business_lighting/faqs/halogen.htm#1

[skids]

1. Same principle is used in thermophotovoltaics.

http://lees.mit.edu/lees/projects/thermophotovoltaics_project.htm

http://www.sc.ic.ac.uk/~q_pv/tpv.html

I don't know if there is a case to be made for these bulbs versus the new LEDS, but maybe...

[eppur_se_muova]

2. VERY interesting link, thanks. nt

[skids]

3. np just added another...

...the first (now 2nd) was more about the cells than the emitter or filter.