Abstract

Three new coded aperture mask designs are proposed. These masks enjoy many of the valuable properties possessed by uniformly redundant arrays and in addition have simple geometric design and few restrictions on size. Decoding arrays for the new designs are given, and an analysis of their noise characteristics is included. Two of the new mask designs are compared with a URA mask when used for imaging phantoms using a conventional hospital gamma camera.

© 1983 Optical Society of America

Full Article  |  PDF Article

References

  • View by:
  • |
  • |
  • |

  1. E. E. Fenimore, T. M. Cannon, AppL. Opt. 17, 337 (1978).
    [CrossRef] [PubMed]
  2. E. E. Fenimore, Appl. Opt. 17, 3562 (1978).
    [CrossRef] [PubMed]
  3. T. M. Cannon, E. E. Fenimore, Appl. Opt. 18, 1052 (1979).
    [CrossRef] [PubMed]
  4. E. E. FenimoreAppl. Opt. 19, 2465 (1980).
    [CrossRef] [PubMed]

1980 (1)

1979 (1)

1978 (2)

Cited By

OSA participates in CrossRef's Cited-By Linking service. Citing articles from OSA journals and other participating publishers are listed here.

Alert me when this article is cited.


Figures (11)

Fig. 1
Fig. 1

A (9 × 9) mask of design I.

Fig. 2
Fig. 2

Decoding array for masks of design I.

Fig. 3
Fig. 3

A (9 × 9) mask of design II.

Fig. 4
Fig. 4

Mask design II on an offset grid.

Fig. 5
Fig. 5

A (9 × 9) mask of design III.

Fig. 6
Fig. 6

A (2 × 2) mosaic of the (9 × 9) III design.

Fig. 7
Fig. 7

Variation in SNR for a single pixel as the source distribution varies between IT1 and IT2.

Fig. 8
Fig. 8

(a) Field of view of camera; (b) variation of SNR with relative source pixel strength.

Fig. 9
Fig. 9

Images of a point source taken with (a) mask design I, (b) mask design III, (c) the quadratic residue mask.

Fig. 10
Fig. 10

Thyroid phantom: (a) quadratic residue mask, (c) mask design I, (c) mask design III.

Fig. 11
Fig. 11

Schematic diagram of thyroid phantom: ⊗, areas of 0% activity; ao-22-24-4042-i001, areas of 100% activity.

Tables (2)

Tables Icon

Table I SNR for Three Mask types

Tables Icon

Table II Effect of Source Displacement

Equations (9)

Equations on this page are rendered with MathJax. Learn more.

α = [ 5 ( n 1 ) n 2 ] / ( n 2 ) , β = 1 / ( n 2 ) ,
α = ( n 2 7 n + 8 ) / ( n 3 ) , β = 2 / ( n 3 ) .
α = ( 11 + 9 n n 2 ) / ( n 4 ) , β = 3 / ( n 4 ) ,
SNR i j = 4 ( n 1 ) S i j { 4 ( n 1 ) S i j + [ α 2 + ( n + 4 ) + 3 ( n 3 ) β 2 ] I T 1 + [ 12 + 4 ( n 4 ) β 2 ] I T 2 + B λ } 1 / 2 ,
λ = { α 2 + 4 ( n 1 ) + [ n 2 4 ( n 1 ) 1 ] β 2 } ,
SNR = 40 S i j ( 40 S i j + 41.63 I T 1 + 24.0 I T 2 + 76.9 B ) 1 / 2 .
SNR = 72 S i j ( 72 S i j + 72 I T + 143 B ) 1 / 2 .
SNR = 6.3 S i j 1 / 2 [ 1 + 1.9 ( B / S i j ) ] 1 / 2 ,
SNR = 8.5 S i j 1 / 2 [ 1 + 2.0 ( B / S i j ) ] 1 / 2 .

Metrics