Digital paper, also known as interactive paper, is patterned paper used in conjunction with a

digital pen A digital pen is an input device which captures the handwriting or brush strokes of a user and converts handwritten analog information created using "pen and paper" into digital data, enabling the data to be utilized in various applications. This ...

to create handwritten digital documents. The printed dot pattern uniquely identifies the position coordinates on the paper. The digital pen uses this pattern to store handwriting and upload it to a computer.

The paper

The dot pattern is a two-dimensional

barcode A barcode or bar code is a method of representing data in a visual, machine-readable form. Initially, barcodes represented data by varying the widths, spacings and sizes of parallel lines. These barcodes, now commonly referred to as linear or o ...

; the most common is the proprietary

Anoto Anoto Group AB (formerly C Technologies) is a Swedish cloud based software provider (SaaS). It primarily dispenses patented dot pattern technology which provides a methodology for accumulating digital big data from analogue inputs. With around ...

dot pattern. In the Anoto dot pattern, the paper is divided into a grid with a spacing of about 0.3 mm, a dot is printed near each intersection offset slightly in one of four directions, a camera in the pen typically records a 6 x 6 groups of dots. The full pattern is claimed to consist of 669,845,157,115,773,458,169 dots, and to encompass an area exceeding 4.6 million km² (this corresponds to 73 trillion unique sheets of letter-size paper). The complete pattern

space Space is the boundless three-dimensional extent in which objects and events have relative position and direction. In classical physics, physical space is often conceived in three linear dimensions, although modern physicists usually cons ...

is divided into various domains. These domains can be used to define paper types, or to indicate the paper's purpose (for example, memo formatting, personal planners, notebook paper, Post-it notes, et cetera). The Anoto dot pattern can be printed onto almost any paper, using a standard printing process of at least 600

dpi A Daytona Prototype International (DPi) was a type of sports prototype racing car developed specifically for the International Motor Sports Association's WeatherTech SportsCar Championship, as their top class of car, acting as a direct replaceme ...

resolution (some claim a required resolution of 1,000 dpi), and

carbon Carbon () is a chemical element with the symbol C and atomic number 6. It is nonmetallic and tetravalent—its atom making four electrons available to form covalent chemical bonds. It belongs to group 14 of the periodic table. Carbon mak ...

-based black ink. The paper can be any shape or size greater than 2 mm to a side. The ink absorbs

infrared light Infrared (IR), sometimes called infrared light, is electromagnetic radiation (EMR) with wavelengths longer than those of visible light. It is therefore invisible to the human eye. IR is generally understood to encompass wavelengths from arou ...

transmitted from the

; the pen contains a receiver that interprets the pattern of light reflected from the paper. Other colors of ink, including non-carbon-based black, can be used to print information that will be visible to the user, and invisible to the pen.

References

{{Paper Computing input devices Paper Display technology

The paper

Further reading

References