A method for improving inspection resolution comprising providing a camera having a flat plane; providing a specific curved surface; providing a series of optical elements (10, 20, 30, 40, 50, 60, 70) and placing the series of optical elements between the specific curved surface and the flat plane of the camera; projecting an image of the specific curved surface onto the flat plane of the camera; characterized in that the step of providing a camera having a flat plane comprises providing a digital camera, and the step of providing a series of optical elements comprises providing a series of optical elements which narrows the depth of field of the digital camera along the specific curved surface, wherein the step of providing the series of optical elements (10, 20, 30, 40, 50, 60, 70) comprises providing a series of seven optical elements, wherein: a front surface radius of a first optical element of the series of seven optical elements is about 51.9mm; a back surface radius of the first optical element of the series of seven optical elements is about -32.0mm; a front surface radius of a second optical element of the series of seven optical elements is about 98.4mm; a back surface radius of the second optical element of the series of seven optical elements is about -15.8mm; a front surface radius of a third optical element of the series of seven optical elements is about -15.8mm; a back surface radius of the third optical element of the series of seven optical elements is about -29.9mm; a front surface radius of a fourth optical element of the series of seven optical elements is about 40.5mm; a back surface radius of the fourth optical element of the series of seven optical elements is about 11.1 mm; a front surface radius of a fifth optical element of the series of seven optical elements is about 11.1 mm; a back surface radius of the fifth optical element of the series of seven optical elements is about -58.1mm; a front surface radius of a sixth optical element of the series of seven optical elements is about 23.5mm; a back surface radius of the sixth optical element of the series of seven optical elements is about -13.5mm; a front surface radius of a seventh optical element of the series of seven optical elements is about -13.5mm; and a back surface radius of the seventh optical element of the series of seven optical elements is about -16.9mm. a front surface radius of a first optical element of the series of seven optical elements is about 51.9mm; a back surface radius of the first optical element of the series of seven optical elements is about -32.0mm; a front surface radius of a second optical element of the series of seven optical elements is about 98.4mm; a back surface radius of the second optical element of the series of seven optical elements is about -15.8mm; a front surface radius of a third optical element of the series of seven optical elements is about -15.8mm; a back surface radius of the third optical element of the series of seven optical elements is about -29.9mm; a front surface radius of a fourth optical element of the series of seven optical elements is about 40.5mm; a back surface radius of the fourth optical element of the series of seven optical elements is about 11.1 mm; a front surface radius of a fifth optical element of the series of seven optical elements is about 11.1 mm; a back surface radius of the fifth optical element of the series of seven optical elements is about -58.1mm; a front surface radius of a sixth optical element of the series of seven optical elements is about 23.5mm; a back surface radius of the sixth optical element of the series of seven optical elements is about -13.5mm; a front surface radius of a seventh optical element of the series of seven optical elements is about -13.5mm; and a back surface radius of the seventh optical element of the series of seven optical elements is about -16.9mm.