Liquid crystal handwriting board, handwriting apparatus, and handwriting system

A handwriting apparatus, comprising:

• a liquid crystal handwriting board, and a control assembly electrically connected to the liquid crystal handwriting board;
• wherein
• the liquid crystal handwriting board comprises:
• a first base plate and a second base plate that are oppositely disposed, and a liquid crystal layer disposed between the first base plate and the second base plate, wherein
• the liquid crystal layer comprises bistable liquid crystal molecules;
• the first base plate comprises:
• a first substrate, and an electromagnetic touch layer and a pixel electrode layer that are disposed on a side of the first substrate, wherein the electromagnetic touch layer is provided with a plurality of electromagnetic signal lines, the plurality of electromagnetic signal lines being sequentially connected in series one by one and a number of the plurality of electromagnetic signal lines being more than two;
• and
• the second base plate comprises:
• a second substrate, and a common electrode layer that is disposed on a side of the second substrate;
• and
• the control assembly is configured to:
• in the case that the liquid crystal handwriting board is in an erasing mode, determine position information of a to-be-erased region by the electromagnetic touch layer, and apply a pixel voltage to pixel electrodes in the to-be-erased region, such that a voltage difference is formed between the pixel electrodes in the to-be-erased region and the common electrode layer.

A handwriting system, comprising:

• an erasing tool and a handwriting apparatus, wherein the erasing tool has a first coil structure;
• and
• the handwriting apparatus comprises:
• a liquid crystal handwriting board, and a control assembly electrically connected to the liquid crystal handwriting board;
• wherein the liquid crystal handwriting board comprises:
• a first base plate and a second base plate that are oppositely disposed, and a liquid crystal layer disposed between the first base plate and the second base plate, wherein
• the liquid crystal layer comprises bistable liquid crystal molecules;
• the first base plate comprises:
• a first substrate, and an electromagnetic touch layer and a pixel electrode layer that are disposed on a side of the first substrate, wherein the electromagnetic touch layer is provided with a plurality of electromagnetic signal lines, the plurality of electromagnetic signal lines being sequentially connected in series one by one and a number of the plurality of electromagnetic signal lines being more than two;
• and
• the second base plate comprises:
• a second substrate, and a common electrode layer that is disposed on a side of the second substrate;
• and
• the control assembly is configured to:
• in the case that the liquid crystal handwriting board is in an erasing mode, determine position information of a to-be-erased region by the electromagnetic touch layer, and apply a pixel voltage to pixel electrodes in the to-be-erased region, such that a voltage difference is formed between the pixel electrodes in the to-be-erased region and the common electrode layer.