I am learning Fourier optics recently and I have a problem of the jinc function.
In optical systems, digital image is blurred with the kernel of jinc function
[itex]h(x,y)=jinc(r)=\frac{J_1(2\pi r / \lambda)}{ 2\pi r / \lambda}[/itex]
in the coherent system, the blurred image
[itex] g(x,y) = |h(x,y) \star f(x,y)|^2 [/itex]
where f(x,y) is the unblurred image and [itex]\star[/itex] indicates the convolution.
I assume we should normalize h, so that we have
[itex] \sum_{x,y} h(x,y) = 1[/itex]
in a discrete form.
And in the incoherent system, the blurred image
[itex] g(x,y) = |h|^2 * |f(x,y)|^2 [/itex]
Do we need to normalize h differently as?
[itex] \sum_{x,y} |h(x,y)|^2 = 1[/itex]
if doing so, it seems that the blurred image is darker in the coherent system. if not, the blurred image in the incoherent system is darker.
which one is correct?
thanks
In optical systems, digital image is blurred with the kernel of jinc function
[itex]h(x,y)=jinc(r)=\frac{J_1(2\pi r / \lambda)}{ 2\pi r / \lambda}[/itex]
in the coherent system, the blurred image
[itex] g(x,y) = |h(x,y) \star f(x,y)|^2 [/itex]
where f(x,y) is the unblurred image and [itex]\star[/itex] indicates the convolution.
I assume we should normalize h, so that we have
[itex] \sum_{x,y} h(x,y) = 1[/itex]
in a discrete form.
And in the incoherent system, the blurred image
[itex] g(x,y) = |h|^2 * |f(x,y)|^2 [/itex]
Do we need to normalize h differently as?
[itex] \sum_{x,y} |h(x,y)|^2 = 1[/itex]
if doing so, it seems that the blurred image is darker in the coherent system. if not, the blurred image in the incoherent system is darker.
which one is correct?
thanks