Hand-held Calculators

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Sharp EL805

Sharp EL-805

and other early Sharp LCD calculators

Sharp calculators with Dynamic Scattering Mode (DSM) Liquid Crystal Displays

Sharp was one of the pioneers of calculators using the DSM (Dynamic Scattering Mode) LCD (Liquid Crystal Display).  These DSM LCDs have the now unusual feature of silver-like reflective digits on a dark background, rather than the now common black digits on a light background.

Although Sharp was one of the pioneers of LCD displays, Rockwell is usually credited with producing the first commercial LCD calculators the previous year, 1972, though these required an internal light source and were much larger; see the Lloyds Accumatic 100.  However, Rockwell quit LCD calculators after a few models whereas Sharp persisted with the development of LCD displays and later produced many models with the now familiar LCD with black digits.

 

'COS' technology

Some of these DSM LCD calculators also employ Sharp's 'COS' (Crystal on Substrate) technology.  This is a method of manufacture used in the early Sharp LCD calculators where the LCD is formed directly on a glass circuit board substrate (see the close-up photographs below) on which the other electronic components are also mounted.  Some subsequent Sharp models with the reflective DSM LCD, although not having the LCD directly formed on the circuit board, are also commonly referred to, incorrectly, as 'COS' models.

The following details of the development of COS and the Sharp EL-805 are based on information kindly supplied by Sharp Corporation:
"A development team headed by Isamu Washozuka had been engaged in developing LCD devices for calculators.  Although Rockwell had already produced some large, desktop, AC-powered LCD calculators, the Sharp team succeeded in integrating CMOS-LSI ICs and LCD devices onto a single glass substrate. This was termed COS or Crystal On Substrate.
Using this technology, the Sharp Compet EL-805 calculator was launched as the world first battery-powered LCD pocket calculator.  This was a breakthrough in the sense that the MOS-LSI and LCD technologies established by this calculator was the starting point for the development of the low-power mobile appliances and personal computers of today."

The true COS (Crystal on Substrate or Calculator on Substrate) calculator has a circuit board which is made of a glass-like ceramic — see the close-up photographs below.  The LCD display is formed directly on this circuit board, which also carries at least two layers of conductive tracks separated by a white, insulating lacquer, and the electronic components.  The glass circuit board has no holes in it, all of the components being surface-mount types.  The user actually looks through the circuit board when viewing the display.

This use of the glass circuit board appears to have been a dead-end in the development of calculators, perhaps because of cost.  Subsequent models from Sharp with this type of display have conventional circuit boards, though their LCD display modules have a similar construction to the display section on the glass circuit boards.

All the Sharp models with displays with reflective LCD characters are often referred to as COS models, though this should really only refer to the early examples with the glass circuit boards.

 

One characteristic of these early DSM (Dynamic Scattering Mode) LCDs with their reflective digits is that they have a hood over the display with a clear window.  This allows ambient light coming at the best angle to be reflected of the digits to give optimal viewing of the display.  These hoods over the display often take the form of a flip-up display cover which also protects the display when the calculators is not in use.

 

The DSM LCD calculators featured on this page are:

Sharp EL-805

Sharp EL-805

The Sharp EL-805, with the display cover open, in operation.

Sharp EL-805

Distinctive features: The first pocket-sized calculator with liquid crystal display (LCD), uses DSM (Dynamic Scattering Mode) LCD with reflective digits.  Also uses Sharp's COS (Crystal on Substrate) technology.

Technical details:
Display is 8 digits, reflective LCD.

4-function.

1.5v (1x AA cell).

80 mm x 120 mm x 21 mm (3.1" x 4.75" x 0.8").

1973. Cost in U.S.A. in December 1973 was US$109.95[1].

Made in Japan.

The Sharp EL-805 of 1973 was the first pocket-sized calculator with a Liquid Crystal display (LCD) and used Sharp's 'COS' (Crystal on Substrate) technology, see the photograph of the Facit 1106 / Sharp EL-805S below.

Sharp EL-805

The Sharp EL-805 with the display cover closed.

Pressing on the lower edge of the cover releases it and also turns on the calculator.

The cover provides physical protection to the LCD, and was perhaps also useful in preventing UV light from possibly damaging the liquid crystal if the calculator was left in sunlight.

Sharp EL805 opened

Here the keyboard, on the right, and the display cover, at the top, have been removed to show the COS circuit board with the DSM LCD.  This is the direction from which the LCD is viewed when the calculator is in use.

Sharp EL805 COS circuit board

The glass-like ceramic COS circuit board has been completely removed from the housing, and shows the DSM LCD digits at the top.

This side of the board has the square conductor matrices of the key contacts.

Low down on the left is a connector linking the copper traces on both sides of the board since there is no through-hole plating here.

Low down on the left is a small circuit board holding conventional wired (i.e. non-surface mount) components.  This daughter circuit board has a connector which connects to conductors on both sides of the main COS circuit board.

Sharp EL805 COS circuit board

Here the COS circuit board has been turned over, viewing the rear of the DSM LCD digits at the top.

Five surface-mount integrated circuits, three square and two round, can be seen.  Also conventional wire-ended resistors and a ceramic capacitor are also soldered to the surface of the conductors which can just be made out under a white coating.

Sharp EL805 COS circuit board

From the side the considerable thickness, almost 3mm, of the ceramic COS circuit board can be seen, with double that thickness at the display.

Some other early Sharp LCD calculators

Facit 1106 / Sharp EL-805S

Facit 1106

Facit 1106 / Sharp EL-805S

Technical details:
Display is 8 digits, reflective LCD.

4-function.

Integrated circuits - Toshiba T3255, T3256, T3288 (here date coded 1974).

1.5v (1x AA cell).

80 mm x 120 mm x 21 mm (3.1" x 4.75" x 0.8").

1973.

Made in Japan.

This Facit 1106 is similar to the Sharp EL-805S, except the casing is black plastic whereas the front of the Sharp EL-805S is brushed metal. The Sharp EL-805 of 1973 was the first calculator with a COS (Crystal on Substrate) LCD (Liquid Crystal Display). A few months later in 1973 the Sharp EL-805S was introduced, with improvements such as a brighter display.
In the late 1960s and early 1970s Sharp produced calculators for the Swedish Facit company. Most are similar to Sharp models but with differently styled casings. This model is based on the Sharp EL-805S.

Facit 1106

With the display cover closed.

Inside Facit 1106

With the rear cover removed showing the surface-mount components and the LCD on the glass circuit board. The user looks through the circuit board (from the other side of course) when operating the calculator.

Sharp EL-808

Sharp EL-808

Sharp EL-808

Technical details:
Display is 8 digits, reflective LCD, with flip-up cover.

4-function.

Main integrated circuits - NEC uPD224C & Sharp IR022 (here date coded 1973).

6v (4x AA).

107 mm x 176 mm x 40 mm (4.25" x 6.9" x 1.6").

About 1973.

Made in Japan.

Sharp EL-8001

Sharp EL-8001

Sharp EL-8001

Technical details:
Display is 8 digits, reflective LCD.

4-function.

Main integrated circuit - NEC uPD224C (here date coded 1973).

6v (4x C).

144 mm x 212 mm x 70 mm (5.7" x 8.5" x 2.75").

About 1973.

Made in Japan.

This is a large calculator designed as a portable desktop model and is too big to fit in a pocket. Surprisingly for a model with LCD display, which have low power consumption, it is powered by 4 large size C cells. Perhaps it was intended to be left powered up all day.

Inside EL-8001

The Sharp EL-8001 with the back cover removed. This shows the conventional phenolic composite circuit board with the integrated circuit mounted towards the top, and the display, seen from the back, as a module which plugs into the green socket.

Sharp EL-8008

Sharp EL-8008
Sharp EL-8008 display

With the display cover flipped up.

Sharp EL-8008

Technical details:
Display is 8 digits, reflective LCD, with flip-up cover.

4-function, %.

1x AA battery.

83x127 mm / 3.25x5.0".

Made in Japan.

Photographs kindly supplied by Jantine Bloemhof.

Sharp EL-8009

Sharp EL-8009

Sharp EL-8009

Technical details:
Display is 8 digits, reflective LCD, with flip-up cover.

4-function.

2x silver oxide button cells.

Folding "clam-shell" style:
Closed 79 x 144 x 11 mm / 3.1 x 5.7 x 0.4".
Open 79 x 73 x 19 mm / 3.1 x 2.9 x 0.75"

Introduced in 1975.

Made in Japan.

Available in 4 different finishes, 2 metallic and 2 leather-type.

The clam-shell design allows full protection for the keyboard and display while giving a very small size.  The calculator is automatically switched on when opened and off when closed.

A brochure for Sharp calculators states for this model "4 different elegant finishes available: metallic gold or silver, or fine leather in brown or red".

Sharp EL-8009S

Sharp EL-8009S

Sharp EL-8009S

Technical details:
Display is 8 digits, reflective LCD, with flip-up cover.

4-function.

2x silver oxide button cells.

Folding "clam-shell" style:
Closed 79 x 144 x 11 mm / 3.1 x 5.7 x 0.4".
Open 79 x 73 x 19 mm / 3.1 x 2.9 x 0.75"

Made in Japan.

Closed

The Sharp EL-8009S closed. It has a light-gold coloured metallic finish.

Sharp EL-8010

Sharp EL-8010
Sharp EL-8010 rear

Sharp EL-8010

Technical details:
Display is 8 digits, reflective LCD, with flip-up cover.

4-function.

2x rechargeable Ni-cad button cells in an assembly, EA-10B. Or, with battery adapter, 2x Silver oxide, or 2x Mercury cells.

76 x 129 x 10 mm (3.0" x 5.1" x 0.4").

Introduced in 1975.

Made in Japan.

Sharp EL-8010

The small size of this calculator, especially the small thickness, allowed it to be one of the first that was provided with a folding case, into which it clips, for protection in the pocket coupled with ease of use.

Sharp EL-8015

Sharp EL-8015

Sharp EL-8015

Technical details:
Display is 8 digits, reflective LCD, with flip-up cover.

4-function, %.

2x rechargeable Ni-cad button cells in an assembly, EA-10B. Or, with battery adapter, 2x Silver oxide, or 2x Mercury cells.

76 x 129 x 10 mm (3.0" x 5.1" x 0.4").

Made in Japan.

Sharp EL-8110

Sharp EL-8110

Sharp EL-8110

Technical details:
Display is 8 digits, reflective LCD, with flip-up cover.

4 function, %, memory, square root.

2x rechargeable Ni-cad button cells in an assembly, EA-10B. Or, with battery adapter, 2x Silver oxide, or 2x Mercury cells.

76 x 129 x 10 mm (3.0" x 5.1" x 0.4").

Made in Japan.

Has gold-coloured metallic casing.

See the article "Liquid Crystal Display (LCD) Calculators" on this site for information about other early LCD calculators.

For further information about Sharp Corporation and its calculators visit the Calculator Companies section of this site.

 

Excellent Youtube videos produced by Michiel de Boer that graphically explain these Liquid Crystal Displays are:

 

Reference

  1. "100-hour calculator", Popular Science, December 1973, p87.

Hand-held Calculators

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© Text & photographs copyright Nigel Tout   2000-2020  except where noted otherwise.