Touchscreen panel with heating function

• US 10,474,289 B2
• Filed: 04/07/2016
• Issued: 11/12/2019
• Est. Priority Date: 04/07/2016
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: Seder, Thomas A., Carpenter, James A., Conway, William E., Ramsey, Reno V., Silvestri, Davide, Degener, George
• Primary Examiner(s): Danielsen, Nathan
• Application Number:
  US15/093,019
• Publication Number:
  US 20170293386A1
• Time in Patent Office: 1,314 Days
• Field of Search: 345156, 345173
• CPC Class Codes: B60K 2360/141 Activation of instrument input devices by approaching fingers or pens
• CPC Class Codes: B60K 2360/1438 Touch screens
• CPC Class Codes: B60K 35/10 Input arrangements, i.e. from user to vehicle, associated with vehicle functions or specially adapted therefor
• CPC Class Codes: G02F 1/132 Thermal activation of liquid crystals exhibiting a thermo-optic effect
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• CPC Class Codes: G02F 1/133382 Heating or cooling of liquid crystal cells other than for activation, e.g. circuits or arrangements for temperature control, stabilisation or uniform distribution over the cell
• CPC Class Codes: G06F 2203/04108 Touchless 2D- digitiser, i.e. digitiser detecting the X/Y position of the input means, finger or stylus, also when it does not touch, but is proximate to the digitiser's interaction surface without distance measurement in the Z direction
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/04164 Connections between sensors and controllers, e.g. routing lines between electrodes and connection pads
• CPC Class Codes: G06F 3/04166 Details of scanning methods, e.g. sampling time, grouping of sub areas or time sharing with display driving Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally G06F3/04184
• CPC Class Codes: G06F 3/041662 using alternate mutual and self-capacitive scanning
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes
• CPC Class Codes: G06F 3/0448 Details of the electrode shape, e.g. for enhancing the detection of touches, for generating specific electric field shapes, for enhancing display quality

Abstract

A touchscreen panel is configured to accept an input touch command. The touchscreen panel includes a liquid crystal display (LCD) layer. The touchscreen panel also includes a touch sensor having a receiving element and a transmitting element, each arranged on the LCD layer. The receiving element and the transmitting element together are configured to detect an impending touch of the touch sensor via a hover system and a touch event in a touch-detecting mode. At least one of the receiving element and the transmitting element is configured to operate in a heating mode, as a heating element, when the impending touch of the touch sensor is not detected. The resultant heating element generates a heat energy input to the LCD layer and accelerates responsiveness of the LCD layer to the touch event. A method of controlling a touchscreen panel is also disclosed.

Claims

1. A touchscreen panel for accepting an input touch command, comprising:

a liquid crystal display (LCD) layer;

a touch sensor including a receiving element and a transmitting element, each arranged on the LCD layer; and

a conducting element arranged on the LCD layer, having multiple electric connections to each of the receiving element and the transmitting element along the receiving and transmitting elements'"'"' respective lengths, and configured to deliver electrical current to each of the receiving and transmitting elements;

wherein;

the receiving element and the transmitting element together are configured to establish mutual capacitance therebetween to thereby detect an impending touch of the touch sensor via a hover system and a touch event in a touch-detecting mode; and

at least one of the receiving element and the transmitting element is configured to operate as a heating element by generating a heat energy input to the LCD layer in a heating mode and accelerate responsiveness of the LCD layer to the touch event when the impending touch of the touch sensor is not detected.

2. The touchscreen panel according to claim 1, further comprising a temperature sensor arranged on the touch sensor and configured to detect a temperature of the LCD layer, and wherein the heating element is additionally configured to generate the heat energy input to the touch sensor in the heating mode when the detected temperature of the LCD layer is below a predetermined value.

3. The touchscreen panel according to claim 2, wherein the touch sensor is additionally configured to switch from the heating mode to the touch-detecting mode, if the impending touch of the touch sensor is detected or the temperature of the LCD layer is at or above the predetermined value.

4. The touchscreen panel according to claim 3, further comprising a conducting element, wherein the touch sensor is in electric communication, via the conducting element, with a power management integrated circuit (PMIC) configured to receive the electrical current from a power supply and regulate the voltage across the heating element to generate the heat energy input to the LCD layer.

5. The touchscreen panel according to claim 4, wherein the PMIC is configured to selectively switch the heating element on in response to the detected temperature of the LCD layer being lower than the predetermined value and switch the heating element off in response to the detected temperature of the LCD layer being at or above the predetermined value.

6. The touchscreen panel according to claim 5, wherein the PMIC is configured to modulate the voltage across the heating element progressively in response to the detected temperature of the LCD layer.

7. The touchscreen panel according to claim 4, wherein the conducting element is one of a wire connection, a trace, and an impression to the LCD layer, and is configured to establish a switchable electric connection of at least one of the receiving element and the transmitting element with the PMIC.

8. The touchscreen panel according to claim 1, wherein the touchscreen panel is a control and a display panel for an infotainment system integrated into a vehicle.

9. The touchscreen panel according to claim 1, wherein each of the receiving element and the transmitting element is configured as an electrode and includes an electrode portion shaped to loop and double back on the LCD layer;

and wherein the electrode portion of the receiving element shaped to loop and double back is configured to complement the electrode portion of the transmitting element shaped to loop and double back, such that the receiving element nests within the transmitting element.

10. The touchscreen panel according to claim 1, wherein solely the receiving element or solely the transmitting element is configured to operate as a heating element.

11. An information processing system comprising:

a touchscreen panel having;

a liquid crystal display (LCD) layer;

a touch sensor having a receiving element and a transmitting element, each arranged on the LCD layer and together configured to establish mutual capacitance therebetween to thereby detect an impending touch of the touch sensor via a hover system and a touch event in a touch-detecting mode;

a conducting element arranged on the LCD layer, having multiple electric connections to each of the receiving element and the transmitting element along the receiving and transmitting elements'"'"' respective lengths, and configured to deliver electrical current to each of the receiving and transmitting elements; and

a temperature sensor arranged on the touch sensor and configured to detect a temperature of the LCD layer;

wherein at least one of the receiving element and the transmitting element is in operative communication with the temperature sensor and configured to operate as a heating element by generating a heat energy input to the LCD layer in a heating mode when the impending touch of the touch sensor is not detected and the detected temperature of the LCD layer is below a predetermined value; and

a power management integrated circuit (PMIC) configured to;

regulate the voltage across the heating element;

switch the touch sensor from the touch-detecting mode to a heating mode, if the impending touch of the touch sensor is not detected and the detected temperature of the LCD layer is below a predetermined value; and

apply, in the heating mode, a voltage across the heating element to thereby generate the heat energy input to the LCD layer and accelerate responsiveness of the LCD layer to the touch event.

12. The information processing system according to claim 11, further comprising a controller in electronic communication with the touchscreen panel and configured to:

receive a signal from the temperature sensor indicative of the detected temperature of the LCD layer;

receive a signal from the hover system indicative of the impending touch of the touchscreen; and

regulate the PMIC in response to the received signals from the temperature sensor and the hover system.

13. The information processing system according to claim 11, wherein the PMIC is additionally configured to switch the touchscreen from the heating mode to the touch-detecting mode, if the impending touch of the touchscreen was detected or the detected temperature of the touchscreen is at or above the predetermined value.

14. The information processing system according to claim 11, wherein the PMIC is configured to selectively switch the heating element on in response to the detected temperature of the LCD layer being lower than the predetermined value and switch the heating element off in response to the detected temperature of the LCD layer being at or above the predetermined value.

15. The information processing system according to claim 14, wherein the PMIC is configured to modulate the voltage across the heating element progressively in response to the detected temperature of the LCD layer.

16. The information processing system according to claim 11, wherein the information processing system is an infotainment system integrated into a vehicle and the touchscreen is a control and a display panel therefor.

17. A method of controlling a touchscreen panel having a liquid crystal display (LCD) layer, the method comprising:

detecting a temperature of the LCD layer via a temperature sensor, wherein the touchscreen panel includes a touch sensor having a receiving element and a transmitting element, each arranged on the LCD layer, together configured to establish mutual capacitance therebetween to thereby detect an impending touch of the touch sensor via a hover system and a touch event in a touch-detecting mode, and at least one of the receiving element and the transmitting element is configured to operate as a heating element by generating a heat energy input to the LCD layer in a heating mode when the impending touch of the touch sensor is not detected;

delivering electrical current to each of the receiving element and the transmitting element via a conducting element arranged on the LCD layer and having multiple electric connection along each of the receiving and transmitting elements'"'"' respective lengths;

scanning for the impending touch of the touch sensor via the hover system;

assessing, via a controller, if the impending touch of the touch sensor has been detected via the hover system and if the detected temperature of the LCD layer is below a predetermined value;

switching, via a power management integrated circuit (PMIC) in operative communication with the controller, from the touch-detecting mode to the heating mode, if the impending touch of the touch sensor has not been detected and the assessed temperature of the LCD layer is below a predetermined value; and

regulating, in the heating mode, via the PMIC, a voltage across the heating element to thereby generate the heat energy input to the LCD layer and accelerate responsiveness of the LCD layer to the touch event.

18. The method according to claim 17, further comprising switching, via the PMIC, from the heating mode to the touch-detecting mode, if the impending touch of the touchscreen is detected or the temperature of the LCD layer is at or above the predetermined value.

19. The method according to claim 17, wherein said regulating the voltage across the heating element includes selectively switching the heating element on in response to the detected temperature of the LCD layer being lower than the predetermined value and switching the heating element off in response to the detected temperature of the LCD layer being at or above the predetermined value.

20. The method according to claim 17, wherein said regulating the voltage across the heating element further includes modulating the voltage across the heating element progressively in response to the detected temperature of the LCD layer.