CROSS-REFERENCE TO RELATED APPLICATION(S)

This application claims priority under 35 U.S.C. § 119 to Korean Patent Application No. 10-2019-0119543, filed on Sep. 27, 2019 in the Korean Intellectual Property Office (KIPO), the disclosure of which is incorporated by reference herein in its entirety.

TECHNICAL FIELD

Exemplary embodiments of the present inventive concept relate to a display apparatus and a method of compensating fingerprint sensing data using the display apparatus. More particularly, exemplary embodiments of the present inventive concept relate to a display apparatus including a fingerprint sensor and a method of compensating fingerprint sensing data using the display apparatus and a compensation function.

DISCUSSION OF THE RELATED ART

Fingerprint recognition devices is one of biometric technologies being widely researched because fingerprint recognition devices are easy to use while providing high security. Recently, the research for fingerprint recognition devices has been conducted to provide devices that are highly reliable at recognizing a user's input of a fingerprint image and making a final determination as to the user's input.

Generally, a fingerprint sensor module acquires the fingerprint image, by using an image capture device, and compares a previously stored fingerprint image with a new input fingerprint image to make the final determination.

When the fingerprint image acquired by the fingerprint sensor module is distorted by a noise component, the accuracy of the final determination may be reduced. To remove the noise component and enhance the sensor characteristic variation, compensation data may be generated using a plurality of test patients. When the number of the test patterns is increased to enhance the reliability of the fingerprint recognition, a capacity of a memory for storing the compensation data may increase. In addition, when the number of the test patterns is increased, an amount of the compensation data may increase.

SUMMARY

According to an exemplary embodiment of the present inventive concept, a display apparatus includes: a display panel configured to display an image; a fingerprint sensor disposed on the display panel and configured to capture a fingerprint image and to generate fingerprint sensing data; and a fingerprint sensor controller configured to generate a compensation characteristic function of each pixel of the fingerprint sensor using a plurality of test patterns, to extract a coefficient of the compensation characteristic function of each pixel and to compensate the fingerprint sensing data using the coefficient of the compensation characteristic function.

In an exemplary embodiment of the present inventive concept, the display apparatus further includes a memory configured to store information including the coefficient of the compensation characteristic function of each pixel.

In an exemplary embodiment of the present inventive concept, as a number of the test patterns used increases, an amount of the information stored in memory does not increase.

In an exemplary embodiment of the present inventive concept, a number of the test patterns is equal to or greater than a degree of the compensation characteristic function.

In an exemplary embodiment of the present inventive concept, the memory is configured to store a coefficient compensation value of each pixel of the fingerprint sensor, wherein a coefficient compensation value of a first pixel of the fingerprint sensor is determined by subtracting a coefficient of the compensation characteristic function of the first pixel from an average of coefficients of the compensation characteristic functions of all of the pixels of the fingerprint sensor.

In an exemplary embodiment of the present inventive concept, the fingerprint sensor controller is configured to generate a first characteristic function of measured fingerprint sensing data, to generate a second characteristic function by adding the coefficient compensation value of each pixel to the coefficient of the first characteristic function and to obtain compensated fingerprint sensing data using the second characteristic function, wherein the fingerprint sensing data is measured by the fingerprint sensor.

In an exemplary embodiment of the present inventive concept, the compensation characteristic function has a form of y=Ax+B.

In an exemplary embodiment of the present inventive concept, a first coefficient compensation value of the first pixel of the fingerprint sensor is determined by subtracting “A” of the first pixel from an average value of “A” of all of the pixels of the fingerprint sensor, wherein a second coefficient compensation value of the first pixel is determined by subtracting “B” of the first pixel from an average value of “B” of all of the pixels of the fingerprint sensor, and wherein the memory is configured to store the first coefficient compensation values of all of the pixels of the fingerprint sensor and the second coefficient compensation values of all of the pixels of the fingerprint sensor.

In an exemplary embodiment of the present inventive concept, a number of the pixels of the fingerprint sensor is M, and a number of the coefficient compensation values is 2M, wherein the number of the coefficient compensation values is independent from a number of the test patterns.

In an exemplary embodiment of the present inventive concept, the compensation characteristic function has a form of y=A×2+Bx+C.

In an exemplary embodiment of the present inventive concept, a first coefficient compensation value of the first pixel of the fingerprint sensor is determined by subtracting “A” of the first pixel from an average value of “A” of all of the pixels of the fingerprint sensor, wherein a second coefficient compensation value of the first pixel is determined by subtracting “B” of the first pixel from an average value of “B” of all of the pixels of the fingerprint sensor, wherein a third coefficient compensation value of the first pixel is determined by subtracting “C” of the first pixel from an average value of “C” of all of the pixels of the fingerprint sensor, and wherein the memory is configured to store the first coefficient compensation values of all of the pixels of the fingerprint sensor, the second coefficient compensation values of all of the pixels of the fingerprint sensor and the third coefficient compensation values of all of the pixels of the fingerprint sensor.

In an exemplary embodiment of the present inventive concept, a number of the pixels of the fingerprint sensor is M, and a number of the coefficient compensation values is 3M, wherein the number of the coefficient compensation values is independent front a number of the test patterns.

According to an exemplary embodiment of the present inventive concept, a method of compensating fingerprint sensing data includes capturing a plurality of test patterns using a fingerprint sensor, wherein the plurality of test patterns are used to generate test sensing data; generating a compensation characteristic function of each pixel of the fingerprint sensor using the test sensing data; extracting a coefficient of the compensation characteristic function; capturing a plurality of fingerprint images using the fingerprint sensor, wherein the plurality of fingerprint images are used to generate fingerprint sensing data; and compensating the fingerprint sensing data using the coefficient of the compensation characteristic function.

In an exemplary embodiment of the present inventive concept, the method further includes storing information including the coefficient of the compensation characteristic function in a memory.

In an exemplary embodiment of the present inventive concept, as a number of the test patterns used increases, an amount of the information stored in the memory does not increase.

In an exemplary embodiment of the present inventive concept, a number of the test patterns is equal to or greater than a degree of the compensation characteristic function.

In an exemplary embodiment of the present inventive concept, the memory is configured to store a coefficient compensation value of each pixel of the fingerprint sensor, wherein a coefficient compensation value of a first pixel of the fingerprint sensor is determined by subtracting a coefficient of the compensation characteristic function of the first pixel front an average of coefficients of the compensation characteristic functions of all of the pixels of the fingerprint sensor.

In an exemplary embodiment of the present inventive concept, compensating the fingerprint sensing data includes generating a first characteristic function of measured fingerprint sensing data, wherein the fingerprint sensing data is measured by the fingerprint sensor; generating a second characteristic function by adding the coefficient compensation value of each pixel to the coefficient of the first characteristic function, and obtaining compensated fingerprint sensing data using the second characteristic function.

In an exemplary embodiment of the present inventive concept, the compensation characteristic function has a form of y=Ax+B.

In an exemplary embodiment of the present inventive concept, a first coefficient compensation value of the first pixel of the fingerprint sensor is determined by subtracting “A” of the first pixel from an average value of “A” of all of the pixels of the fingerprint sensor, wherein a second coefficient compensation value of the first pixel is determined by subtracting “B” of the first pixel from an average value of “B” of all of the pixels of the fingerprint sensor, and wherein the memory is configured to store the first coefficient compensation values of all of the pixels of the fingerprint sensor and the second coefficient compensation values of all of the pixels of the fingerprint sensor.

