The world has witnessed remarkable progress in the development of electrical light sources. Since the year 1880 the main source of lighting in the home has been the incandescent lamp, which is commonly referred to as a light bulb. Marked improvements were made when the filament material was changed from carbon to tungsten and the lamp interior changed from vacuum to an inert gas filling. However, it appeared that significant improvement in the lamp might not be achievable after about the year 1959 when the vertically oriented filament was introduced. Although the halogen lamp was introduced as well as the halogen lamp with an infrared coating on the bulb, these products did not make a serious inroad into the replacement of incandescent lamps in the home. It took a global shakeup regarding energy availability and cost to result in the next lamp type to be used in the home.

The oil embargo of 1973-1974 prompted some effort to achieve higher efficacy in light sources. In addition, the melting of the polar ice caps has, at last, convinced most people that serious conservation measures need to be taken in the utilization of limited fossil fuels.

One person who could see the need for change was Edward E. Hammer, a lamp engineer in the Fluorescent Engineering Department of the General Electric Company at the Lighting Business Headquarters at Nela Park in East Cleveland, Ohio. Early in his career Hammer worked directly under Richard Thayer^{3, 4} (1907-1992), a pioneer in fluorecent lamp development, as well as alongside Eugene Lemmers⁵ (1907-1992) and John Aicher⁶ (1912-1993), also fluorescent lamp pioneers. Hammer served as group coordinator for several successful energy saving projects, such as the F-40 Watt Miser lamp, which consisted of the standard linear four-foot T12 bulb (1.5 inches in diameter). Hammer was interested in determining if he could develop a fluorescent lamp that might replace the incandescent light bulbs used in portable lamps, for example. Any such design had constraints that could result in failure. For example, a design would require a glass tube that had to have considerable length. The coiling of the tubing into a helical, or spiral, shape seemed to be a reasonable approach to the problem. However, it took considerable talent on the part of the glass worker in the model shop to confine the tubing to the space desired. Nevertheless, Hammer was successful in his design attempts. However, the idea of manufacturing a helical fluorescent tubing lamp had to be approved by management.

It was decided by management not to pursue the manufacture of the helical tube fluoresecnt lamp. The manufacturing setup cost would have been in the millions of dollars⁷ and such a cost at that time was not desirable. In part this was due to the fact that the manufacture of a tube into that shape seemed to be quite a challenge. The lamp itself was to be kept proprietary and so Hammer did not apply for a patent on it. However, in hind sight that might have been a mistake. Lamps displaying the helical tubing were visible in Hammer's laboratory and it is believed that a visitor to Nela Park saw the lamp prototypes and carried this information back to a rival company - even though confidentiality agreements should have prevented this from happening. Hammer's work with the helical lamp occurred in the 1975-6 time frame. In 1992 GE did build a machine but the lamp did not go into mass production because of difficulty in controlling the process⁸.

The 1976 lamp prototype utilizing the helical glass tubing is shown with Hammer's photograph above. A similar Hammer helix is now on exhibit at the Smithsonian Institution in Washington, D. C. and is shown to the left⁹. The Smithsonian lamp identification is: S. I. image #lar2-2d1.

Let us take a look backward to the 28th of March 1980, when the Philips Company introduced the first marketed non-helical compact fluorescent lamp (CFL) at a press conferences in Amsterdam and New York¹⁰. It was known as the SL18². The tubing consisted of straight sections bridged together at the one end. The lamp employed a magnetic ballast, which made the unit rather heavy.

About 1995, Shanghai Xiangshan, a Chinese firm, was the first to form the helical coil and achieve success in the marketplace⁸. Apparently a large number of glass blowers were employed to produce the helices. This approach to the manufacturing problem was possible because of the lower labor rates in China.

Other companies, including General Electric, were finally able to develop workable machinery. In the mid 1990s a company known as Technical Consumer Products (TCP), which is located in Aurora, Ohio, started to make the helical tubing required in the lamp and the product proved successful. In the year 2006 improvements were made and the TCP daily output is now about 1.5 million lamps⁷.

Two samples of General Electric helical lamps are shown below. Comparison of size is made with a standard 60-watt light bulb.

The contributions to the design of lamp types by Ed Hammer can be appreciated by viewing the patents issued in his name. Patents granted to Hammer follow^{11, 12}.