Open close detection for foldable displays

1 . A method comprising:

measuring raw data by simultaneously driving a plurality of channels of a foldable touchscreen device, wherein the foldable touchscreen device includes a first touchscreen portion, a second touchscreen portion, and a hinge connecting the first touchscreen portion and the second touchscreen portion;

collecting the raw data from a first channel on the first touchscreen portion and a second channel on the second touchscreen portion of the device, the first channel being positioned opposite from the second channel relative to a folding axis of the foldable touchscreen device;

determining a distance between the first channel and the second channel based on the collected raw data;

generating a baseline capacitance based on the distance between the first channel and the second channel;

filtering the generated baseline capacitance;

calculating strength data based on the filtered baseline capacitance and the collected raw data; and

determining a folding state based on the calculated strength data.

2 . The method of claim 1 , wherein measuring the raw data comprises:

simultaneously driving a plurality of force channels;

receiving a signal from a plurality of sense channels; and

measuring a mutual capacitance between the force channels and the sense channels.

3 . The method of claim 2 , wherein the mutual capacitance is inversely proportional to the distance between the first channel and the second channel.

4 . The method of claim 2 , wherein the force channels are perpendicular to the folding axis and wherein the sense channels are parallel to the folding axis.

5 . The method of claim 1 , wherein the first channel extends along a first edge of the foldable touchscreen device and the second channel extends along a second edge of the foldable touchscreen device.

6 . The method of claim 5 , wherein measuring the raw data comprises:

simultaneously driving a plurality of sense channels;

receiving a signal from a plurality of force channels; and

measuring a mutual capacitance between the sense channels and the force channels, wherein the mutual capacitance is inversely proportional to the distance between the first edge of the foldable touchscreen device and the second edge of the foldable touchscreen device.

7 . The method of claim 6 , wherein the sense channels are perpendicular to the folding axis and the force channels are parallel to the folding axis.

8 . The method of claim 1 , wherein generating the baseline capacitance comprises setting the baseline capacitance equal to the raw data when the distance between the first channel and the second channel indicates the folding state is open.

9 . The method of claim 1 , wherein generating the baseline capacitance comprises setting the baseline capacitance equal to the raw data and an offset when the distance between the first channel and the second channel indicates the folding state is closed.

10 . The method of claim 1 , wherein the strength data is a difference between the filtered baseline capacitance and the raw data.

11 . The method of claim 1 , wherein determining the folding state comprises:

determining that the folding state is closed when the calculated strength data is greater than a predetermined threshold; and

determining that the folding state is open when the calculated strength data is less than or equal to the predetermined threshold.

12 . The method of claim 11 , wherein determining the folding state comprises:

determining a previous folding state based on previous calculated strength data;

determining that the folding state is closed when the previous folding state is open and the calculated strength data is greater than or equal to a predetermined high threshold or the calculated strength data is less than or equal to a predetermined low threshold;

determining that the folding state is closed when the previous folding state is closed and the calculated strength data is greater than the predetermined low threshold and less than the predetermined high threshold;

determining that the folding state is open when the previous folding state is closed and the calculated strength data is greater than or equal to the predetermined high threshold or the calculated strength data is less than or equal to the predetermined low threshold; and

determining that the folding state is open when the previous folding state is open and the calculated strength data is greater than the predetermined low threshold and less than the predetermined high threshold.

13 . A method comprising:

collecting raw data from a first edge of a first touchscreen portion and a second edge of a second touchscreen portion of a foldable touchscreen device over a plurality of frames, the first edge being positioned opposite from the second edge relative to a hinge connecting the first touchscreen portion and the second touchscreen portion of the foldable touchscreen device;

generating a baseline capacitance based on an average of the collected raw data;

calculating strength data based on a difference between a current raw data and the average of the collected raw data;

integrating the strength data over a noise level;

comparing the integrated strength data with an open/close threshold; and

changing an open/close folding state from a previous open/close folding state when the integrated strength data is greater than or equal to the open/close threshold.

14 . The method of claim 13 , wherein collecting the raw data from the first edge of the first touchscreen portion and the second edge of the second touchscreen portion comprises:

simultaneously driving a plurality of force channels;

receiving a signal from a plurality of sense channels; and

measuring a mutual capacitance between the force channels and the sense channels.

15 . The method of claim 14 , wherein the mutual capacitance is inversely proportional to a distance between the first edge and the second edge.

16 . The method of claim 14 , wherein the force channels are perpendicular to the hinge and the sense channels are parallel to the hinge.

17 . The method of claim 13 , wherein collecting the raw data from the first edge of the first touchscreen portion and the second edge of the second touchscreen portion comprises:

simultaneously driving a plurality of sense channels;

receiving a signal from a plurality of force channels; and

measuring a mutual capacitance between the sense channels and the force channels, wherein the mutual capacitance is inversely proportional to a distance between the first edge and the second edge.

18 . The method of claim 17 , wherein the sense channels are perpendicular to the hinge and the force channels are parallel to the hinge.

19 . A device comprising:

a first touchscreen portion;

a second touchscreen portion;

a hinge connecting the first touchscreen portion and the second touchscreen portion; and

a touch controller configured to:

simultaneously drive a plurality of drive channels to measure raw data;

receive raw data from a first receive channel of the first touchscreen portion and a corresponding second receive channel of the second touchscreen portion, wherein the first receive channel and the second receive channel are perpendicular to the drive channels;

determine a distance between the first receive channel and the second receive channel;

generate a baseline capacitance based on the distance between the first receive channel and the second receive channel;

filter the generated baseline capacitance;

calculate strength data based on the filtered baseline capacitance and the raw data; and

determine a folding state based on the calculated strength data.

20 . The device of claim 19 , wherein the first receive channel is on an outer edge of the first touchscreen portion and the second receive channel is on an outer edge of the second touchscreen portion.

21 . The device of claim 19 , wherein the touch controller is further configured to:

determine that the folding state is closed when the calculated strength data is greater than a predetermined threshold; and

determine that the folding state is open when the calculated strength data is less than or equal to the predetermined threshold.

22 . The device of claim 19 , wherein the touch controller is further configured to:

determine a previous folding state based on previous calculated strength data;

determine that the folding state is closed when the previous folding state is open and the calculated strength data is greater than or equal to a predetermined high threshold or the calculated strength data is less than or equal to a predetermined low threshold;

determine that the folding state is closed when the previous folding state is closed and the calculated strength data is greater than the predetermined low threshold and less than the predetermined high threshold;

determine that the folding state is open when the previous folding state is closed and the calculated strength data is greater than or equal to the predetermined high threshold or the calculated strength data is less than or equal to the predetermined low threshold; and

determine that the folding state is open when the previous folding state is open and the calculated strength data is greater than the predetermined low threshold and less than the predetermined high threshold.