Who invented low energy light bulbs

There has been much resistance, however, to these policies owing to the low cost of incandescent bulbs, the instant availability of light and concerns of mercury contamination with CFLs. Here at Bulbs. The many benefits of LED technology are summed up in this video. Skip to content. Account Sign In. Instant Rebates are available to businesses Click to find out about your location.

BulbFinder Our easy-to-use BulbFinder will let you find the correct bulb, step by step. Worcester, MA Tel. Learn about the humble light bulb, how it came into being and how it has developed over the years.

Ballasts and Dimmers - What do I need to know? Original carbon-filament bulb from Thomas Edison. Sign up to receive our best offers Subscribe. Many manufacturers have tried different designs, but the shape Hammer coined remains dominant. Hammer invented the bulb in , he said, and primarily worked alone. Editor's note: the years reflect the time Hammer says he invented the bulbs, not when GE announced them. The original prototype is in the Smithsonian. Although executives at GE liked the idea, they decided not to market it at the time.

The electronics giant contemplated licensing the design. Unfortunately, the design leaked out. Others copied it before GE started a licensing program. Hammer hasn't done badly either. He has published more than 40 papers and was awarded the Edison Medal by the Institute for Electrical and Electronics Engineers in For the summer and winter exposures, the hazard ratio was 1.

This parameter is useful for assessing similar sources that may vary in luminance, but have identical emission spectra: it permits an assessment of the blue light hazard by measuring the luminance. The panel lamp was 1. The blue light to luminance hazard ratios were similar for the domestic lamps, ranging from 2. The panel lamp had a ratio of 5.

Screens were divided into computer monitors, laptop screens, tablet computers, and smartphones. All devices were set to maximum brightness. After the first batch of measurements, it was clear that the highest luminance and blue light spectral irradiance occurred from a white screen. Any other colours were generated by removing part of the emission from the device. Therefore, only the worst case, white screen results are presented in Table 1. However, the luminance of the LEDs was over twice this value.

The blue light weighted radiance limit for long-term viewing was exceeded by a factor of up to three. Humans have evolved under natural light from the sun. Intentional staring at the sun causes eye injuries, as is reported after solar eclipses. Comparing natural exposures with the reasonably foreseeable exposure to optical radiation from lamps, computer screens and mobile devices, such as smartphones shows that the actual spectrally weighted irradiance is lower than the natural exposures.

For sources with similar emission spectra, it is possible to measure the luminance and predict the blue light hazard, as the ratio of blue light weighted irradiance to luminance is approximately constant for a given type of source. In conclusion, under even extreme long-term viewing conditions, none of the assessed sources suggested cause for concern for public health.

The worst assessed source consisted of three indicator LEDs, which were unlikely to be viewed close up for long enough to cause concern. However, these sources were representative of indicator lamps that did not require the assessed luminance for their intended function. The percentage transmission of blue light from the corneal surface to the retina is age related, with the transmission for children higher than for adults. The impact of the blue light from the studied sources on circadian rhythm and sleep quality was outside of the scope of this study.

Photoprotective effects of blue light absorbing filter against LED light exposure on human retinal pigment epithelial cells in vitro. J Carcinog Mutagen S6: doi Retinal sensitivity to damage from short wavelength light. Nature ; : — Article Google Scholar. International Commission on Non-ionizing Radiation Protection. Guidelines on limits of exposure to incoherent visible and infrared radiation. Health Phys ; : 74— Guidelines on limits of exposure to incoherent optical radiation 0.

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Eye ; 16 : — Erratum 1: Vienna, Austria, Download references. You can also search for this author in PubMed Google Scholar.