Calculator watch financial functions (in the Casio CBA-10). Usually calculator watch operates with eight digits number, however, calculator watch can operate with 6 digits (for example, Casio C-801) or 10 digits (Casio CBA-10) numbers. Calculator watches first appeared in the mid 1970s introduced by Pulsar (1975, then a brand of the Hamilton Watch Company) and Hewlett Packard. Several watch manufacturers have made calculator watches over the years, such as Pulsar and Timex, but the Japanese electronics company Casio produced the largest variety of models. In the mid-1980s, Casio created the Databank calculator watch, which not only performed calculator functions, but also stored
Solar-powered calculator in modern TI calculators is denoted by a lower case "a" at the end of the model number (e.g. TI-30a). In older models, such as the TI-36 Solar, "Anylite Solar" is printed on the calculator. As of the 2010s, some very cheap calculators include a "dummy" solar panel, implying that they are solar-powered, when they are actually powered only by battery. Solar-powered calculator Solar-powered calculators are hand-held electronic calculators powered by solar cells mounted on the device. They were introduced at the end of the 1970s. Amorphous silicon has been used as a photovoltaic solar cell material for devices which