Examples Of Ambiguism In The Mask Of - amazonia.fiocruz.br

Examples Of Ambiguism In The Mask Of Video

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By continuing to use this site, you agree to our use of cookies. We've also updated our Privacy Notice. Click here to see what's new. We designed an optical—digital system that delivers near-diffraction-limited imaging performance with a large depth of field. This system is the standard incoherent optical system modified by a phase mask with digital processing of the resulting intermediate image.

Adam Sennet

The phase mask alters or codes the received incoherent wave front in such a way that the point-spread function and the optical transfer function do not change appreciably as a function of misfocus. Focus-independent digital filtering of the intermediate image is used to produce a combined optical—digital system that has a nearly diffraction limited point-spread function. link

This high-resolution extended depth of field is obtained through the expense of an increased dynamic range of the incoherent system. We use both the ambiguity function and the stationary-phase method to design these phase masks.

1. Introduction

Extending the see more of field of incoherent optical systems has been an active research topic for many years. A unique method of achieving an extended depth of field without an apodizer [6] was described in The major shortcoming of this method is that the focus must be varied during exposure. We describe a novel method for extending the depth of field of incoherent optical systems that does not suffer from the significant deficiencies of earlier methods.

Our method employs a phase mask to modify the incoherent optical system in such a way that the point-spread function PSF is insensitive to misfocus, while the optical transfer function OTF has no regions of zero values within its passband.

However, because the OTF has no regions of zeros, digital processing can be used to restore the sampled intermediate image. Further, because the OTF is insensitive to misfocus, the same digital processing restores the image for all values of misfocus.

This combined optical—digital system produces a PSF that is comparable to that of the diffraction-limited PSF but over a far larger region of focus.]