The purpose of the website is to give an idea of the chronology of the design history of the solar wristwatch. This site was launched in September of 2006 and is a work in progress as I learn more.
The focus of this website is on the early period of solar watch development: the twenty four-year period between 1972 to 1995. This is the span of time between the introduction of the first solar wristwatch, the Synchronar, and the introduction of the Citizen Eco-Drive line in 1995.
The design evolution has for the most part been what could be called “design conformance” or “design regression.” The earlier solar watch designs showed imagination and creativity. There seemed to be a greater spirit of inventiveness in the design spirit of the timepieces of the earlier period. Over time the primarily trend has been about making solar watches look like other watches.
The most interesting and innovative designs came earliest – the Synchronar, Nepro and the Sicura LCD. There have been some interesting points along the way – some Junghans models and the Lorus LCD. Generally, the design evolution of the solar watch has been to make them look like conventional watches. The earlier watches had to deal with an array of solar cells. When this technological problem of the size and efficiency of the solar cells was solved, designers chose to conform to the design of all other watches.
This design history of the solar watch ends in 1995 with the introduction of the Citizen Eco-Drive line. Solar watches from this period on have technological advantages over most early solar watches. However, since 1995 solar watches have been indistinguishable from their battery powered or mechanical powered counterparts.
This website not meant to be an exhaustive collection of all makes and models of solar watches – just the most interesting and significant that I have been able to find. In addition, I have tried to show the chronology and examples of solar watch “firsts” - the first solar LED, the first solar LCD, the first solar analog, and the first solar atomic.
The charts shows the activity for each year. It is sometimes difficult to determine the year of the watch. In some cases, I have found the year the watch was introduced at the Basle Fair. Sometimes I have only found a date when the watch went on sale first. Other times I have made a subjective estimate of the date based on the style of the watch.
There are three categories of watches:
I. LED – digital: watches that used cells to power or assist the battery to power an light emitting diode (LED) digital display
II. LCD – digital: watches that used cells to power or assist the battery or capacitor to power an liquid crystal display (LCD) digital display
III. Analog - watches that used cells to power or assist the battery or capacitor to power an analog (i.e., traditional watch hands) display. These have all been mechanical hands except one LCD watch model with an analog hand display (Citizen Solar Sensor, 1982).
This organization of the watches does not take into account the evolution of the technology behind the layout. Over time this evolved as well. The earliest watch was the Synchronar that used solar cells to charge nic-cad batteries sealed in a case which was not designed to be opened. Most other early watches were primary driven by a battery which could be replaced. The solar cell provided supplemental power. Later watches tend to use the solar cells to charge capacitors and did not require any battery or replacement.
Initially solar watches used single crystal silicon cells – gray cells. RCA developed amorphous silicon solar cells which were much more efficient and a deep blue color. Beginning in 1995 Seiko developed a way to place the solar cell under the face and using a great variety of materials and colors on the face.
Over time with technological advances, the solar panels no longer have to be taken into account in the case design. Michel Froelicher and Rene Jacques have written a history of alternative power sources for watches and cover the developement of the solar watch. They note: "On ne voit plus les cellules photovoltaïques et on les oublie dans la conception de la montre." ("One does not see any more of the photovoltaic cells and one forgets them in the design of the watch.") LES ÉNERGIES RENOUVELABLE DANS LA MONTRE
Watchismo Times has done an excellent overview of solar watches in the January 22, 2007 article http://watchismo.blogspot.com/2007/01/top-10-vintage-solar-powered-watches.html
Are there factual errors or incomplete information on this site? I suspect there are. Please send me an email to correct or add what you know. email@example.com
Acknowledgements – This website owes a great deal to the work of other who have gathered a peculiar knowledge and have been willing to share it:
Glenn Crooker, Casio Inc.
Frank Filangeri, Manufacturing Manager, Uranus Watch
Allyson Gottlieb, Citizen Watch Company of America
Paul Grimwood, Citizen Watch Company of New Zealand
Marlène Rufenacht, Archiviste-Documentaliste, Musée d'Horlogerie du Locle
Roger and Howard Riehl
Haruo Saito, Orient Watch Co. Ltd.
Amabda Waite, London Museum
Anne Thierrin Zampieri of CENTREDOC
Two publications have been very helpful:
WatchTime Special Issue: All About Citizen Fall 2002
Watch by Pieter Doensen, Snoeck-Ducaju & Zoon, 1994.
To purchase this book contact http://www.xs4all.nl/~rkeulen/watch/moreinfo.html
I have tried to collect information about the dates and specifications of the watches for others trying to understand the development of the solar watch. While it is hard sometimes to seperate fact from opinion, I have tried to indicate my most subjective comments about the watches in italics.