Accession Number:

ADA505842

Title:

Point and Beam Spread Functions of Seawater

Descriptive Note:

Book chapter

Corporate Author:

NAVAL RESEARCH LAB STENNIS SPACE CENTER MS OCEANOGRAPHY DIV

Personal Author(s):

• Hou, Weilin

Report Date:

2009-08-13

Pagination or Media Count:

5.0

Abstract:

The point spread function PSF describes response of a linear optical imaging system to a point light source see Point spread function and imaging in turbid medium. This response includes the effects of both the image system itself lens, mirror, recording media, etc. and of the medium the optical signal lasses through for example, seawater. By using the concept of the PSF, closely related to BSF, effects of different components of such a linear system can be separately modeled and multiplicatively accounted for in the spatial frequency domain. Mathematically, an image, gx, y, of an object is the combination of the original signal image, f x, y, convolved with the PSF of the entire imaging system, hx, y, and of the noise, nx, y gx, y f x, y hx, y nx, y where coordinates x. y indicate a position in the image and the symbol denotes the operation of convolution. If the PSF is shift invariant, the convolution of and h in the spatial domain corresponds to a simple multiplication of the Fourier transforms, fF and gF, of f and h, respectively. This is referred to a the convolution theorem for example httpmathworld.wolfram.comConvolutionTheorem.html.

Descriptors:

• *FUNCTIONS(MATHEMATICS)
• *OPTICAL IMAGES
• *CONVOLUTION
• *SEA WATER
• SIGNALS
• SHIFTING
• INVARIANCE
• FREQUENCY DOMAIN
• MULTIPLICATION
• THEOREMS
• TURBIDITY
• LIGHT SOURCES
• OPTICS
• POINTS(MATHEMATICS)
• FOURIER TRANSFORMATION
• LINEAR SYSTEMS

Subject Categories:

• Physical and Dynamic Oceanography
• Numerical Mathematics
• Optics
• Radiofrequency Wave Propagation

Distribution Statement:

APPROVED FOR PUBLIC RELEASE