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Emergence of new industries from evolving technologies is critical to the global economy, yet has been relatively understudied due to the paucity of available data. This study draws lessons on industry emergence, by analyzing how a solid-state lighting (SSL) industry grew out of light emitting diode (LED) technologies that evolved for half a century, with participation by tens of thousands of researchers in universities, national laboratories, and firms. Using data on publications, patents, and firms combined with business history we trace the evolution of SSL through a succession of market niches. At times a few researchers with unorthodox research approaches made breakthroughs that greatly advanced particular technology trajectories and pushed LED research in unexpected directions. A succession of LED market niches advanced the technology and provided profits to incentivize continuing research while reducing cost and improving efficacy of LEDs. Innovating firms developed a thicket of patents and captured substantial profit, but were embroiled in extensive litigation that was ultimately resolved through cross-licensing. A major new generation of lighting products is now disrupting the traditional lighting industry. Although the leading incumbent lighting firms all invested early and heavily in SSL, the industry's future leadership is uncertain. 相似文献
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L.L. Holladay 《Journal of The Franklin Institute》1929,207(2):193-230
With the growth of the science of light and vision, the engineer has been putting forth some effort to use daylight to a greater advantage. In our endeavor to use natural and artifical light in a more economical manner, it becomes necessary to know the initial and operating costs of each. The determination of the initial cost of natural lighting is made by computing the difference in cost between a building equipped with natural and artifical lighting and a building of similar construction equipped merely with artificial lighting.Though it may be possible to dispense with natural lighting, it would hardly be possible to dispense with artificial lighting if work is to be pursued for eight hours a day throughout the year; for natural light is of no greater constancy than daylight itself.The major items entering into the initial cost of natural lighting equipment per 100 sq. ft. of floor area under normal conditions vary from a minimum in one type of standard building to a maximum in another type as follows:
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| Minimum | Maximum | ||
| Windows and structure | $ 0.00 | to | $45.00 |
| Heating equipment | 10.30 | to | 32.10 |
| Light-courts | 8.40 | to | 45.30 |
| Total for all three items for standard buildings | 28.56 | to | 79.90 |