Apparatus for displaying drawings

An apparatus for displaying a drawing, said apparatus comprising:

• a display member having a viewing surface;
• support means for supporting said display member adjacent a surface with said viewing surface facing away from said surface;
• an electro-optic medium having first and second display states differing in at least one optical property, said medium being changed from its first to its second display state by application of an electric field to said medium, said electro-optic medium being disposed on said display member so as to be visible to an observer viewing said viewing surface;
• a writing head arranged to write on said electro-optic medium an image visible to the observer viewing said viewing surface;
• and
• drive means for moving said writing head relative to said electro-optic medium,
• wherein said display member has the form of a hollow box, said electro-optic medium is disposed on an internal surface of said box, the portion of said box adjacent said electro-optic medium being substantially transparent so as to enable an observer to see said electro-optic medium through said viewing surface, said writing head comprises a stylus member, and said drive means are arranged to move said writing head in two dimensions over said electro-optic medium.

An apparatus for displaying a drawing, said apparatus comprising:

• a display member having a viewing surface;
• support means for supporting said display member adjacent a surface with said viewing surface facing away from said surface;
• an electro-optic medium having first and second display states differing in at least one optical property, said medium being changed from its first to its second display state by application of an electric field to said medium, said electro-optic medium being disposed on said display member so as to be visible to an observer viewing said viewing surface;
• a writing head arranged to write on said electro-optic medium an image visible to the observer viewing said viewing surface;
• and
• drive means for moving said writing head relative to said electro-optic medium,
• wherein said display member has the form of a hollow box, said electro-optic medium is disposed on a movable member within said box, said writing head is disposed at a fixed location within said box, and said drive means is arranged to drive said movable member past said fixed writing head.

An apparatus for displaying a drawing, said apparatus comprising:

• a display member having a viewing surface;
• support means for supporting said display member adjacent a surface with said viewing surface facing away from said surface;
• an electro-optic medium having first and second display states differing in at least one optical property, said medium being changed from its first to its second display state by application of an electric field to said medium, said electro-optic medium being disposed on said display member so as to be visible to an observer viewing said viewing surface;
• a writing head arranged to write on said electro-optic medium an image visible to the observer viewing said viewing surface;
• and
• drive means for moving said writing head relative to said electro-optic medium,
• the apparatus further comprising data storage means for storing data representing a plurality of drawings, and data selection means for selecting at least one of said plurality of drawings for writing by said writing head on said electro-optic medium.

An apparatus for displaying a drawing, said apparatus comprising:

• a display member having a viewing surface;
• support means for supporting said display member adjacent a surface with said viewing surface facing away from said surface;
• an electro-optic medium having first and second display states differing in color perceptible to the human eye, said medium being changed from its first to its second display state by application of an electric field to said medium, said electro-optic medium being disposed on said display member so as to be visible to an observer viewing said viewing surface;
• a writing head arranged to write on said electro-optic medium an image visible to the observer viewing said viewing surface;
• and
• drive means for moving said writing head relative to said electro-optic medium.