K. Dabighi - Department of mathematic, Kerman Branch, Islamic Azad University, Kerman, ‎Iran.‎
A. Nazari - Department of Mathematics, Faculty of Mathematics and Computer Sciences, Shahid Bahonar University, Kerman,‎ Iran‎.
S. Saryazdi - Department of Electrical Engineering, Shahid Bahonar University, Kerman, ‎Iran‎.
V. Momenaei - Department of Mathematic, Kerman Branch, Islamic Azad University, Kerman, ‎Iran‎.

In this study, we review the elliptic differential operators and filters, and due to a wide range of elliptic operators, focus on a batch of elliptic operators with constant coefficients second order and then generalizing them to a higher order. Finally by discretization of the elliptic operators, we express and prove two theorems and show that the obtained filters are the high pass.

filters, high pass filter, differential operator, principal symbol, Elliptic ‎operators.‎