Multileaf collimator with alternating trapezoidal leaf geometry design

1. A multileaf collimator, comprising:

a plurality of beam-blocking leaves of a first type, each of the plurality of beam-blocking leaves of the first type having a trapezoidal geometry viewed in a longitudinal moving direction with a first lateral side, a second lateral side, a wider end, and a narrower end, the wider end being proximal to a source;

a plurality of beam-blocking leaves of a second type, each of the plurality of beam-blocking leaves of the second type having a trapezoidal geometry viewed in the longitudinal moving direction with a first lateral side, a second lateral side, a wider end, and a narrower end, the wider end being distal to the source; and

the plurality of beam-blocking leaves of the first type being alternatingly arranged with the plurality of beam-blocking leaves of the second type side by side.

2. The multileaf collimator of claim 1 , wherein

first lateral sides of the plurality of beam-blocking leaves of the first type align to converge to a first point offset from the source, and

second lateral sides of the plurality of beam-blocking leaves of the first type align to converge to a second point offset from the source and opposite to the first point.

3. The multileaf collimator of claim 2 , wherein

wherein a first lateral side of a beam-blocking leaf of the second type is adjacent to a second lateral side of a beam-blocking leaf of the first type, and a second lateral side of a beam-blocking leaf of the second type is adjacent to a first lateral side of a beam-blocking leaf of the first type, and

first lateral sides of the plurality of beam-blocking leaves of the second type align to converge to the second point, and second lateral sides of the plurality of beam-blocking leaves of the second type align to converge to the first point.

4. The multileaf collimator of claim 3 , wherein the first point offsets from the source at a distance substantially equal to a distance that the second point offsets from the source.

5. The multileaf collimator of claim 1 , wherein a first lateral side and a second lateral side of each of the plurality of beam-blocking leaves of the first type, and a first lateral side and a second lateral side of each of the plurality of beam-blocking leaves of the second type are substantially flat.

6. The multileaf collimator of claim 5 , wherein the first point offsets from the source at a distance substantially equal to a distance that the second point offsets from the source.

7. The multileaf collimator of claim 1 , wherein a first lateral side and a second lateral side of each of the plurality of beam-blocking leaves of the first type, and a first lateral side and a second lateral side of each of the plurality of beam-blocking leaves of the second type are substantially flat.

8. A multi-level multileaf collimator (MLC), comprising:

a first MLC in a first level distal to a source; and

a second MLC in a second level proximal to the source,

wherein the second MLC comprises:

a plurality of beam-blocking leaves of a first type, each of the plurality of beam-blocking leaves of the first type having a trapezoidal geometry viewed in a longitudinal moving direction with a first lateral side, a second lateral side, a wider end and a narrower end, the wider end being proximal to the source;

a plurality of beam-blocking leaves of a second type, each of the plurality of beam-blocking leaves of the second type having a trapezoidal geometry viewed in the longitudinal moving direction with a first lateral side, a second lateral side, a wider end, and a narrower end, the wider end being distal to the source; and

the plurality of beam-blocking leaves of the first type being alternatingly arranged with the plurality of beam-blocking leaves of the second type side by side.

9. The multi-level multileaf collimator of claim 8 , wherein

first lateral sides of the plurality of beam-blocking leaves of the first type align to converge to a first point offset from the source, and

second lateral sides of the plurality of beam-blocking leaves of the first type align to converge to a second point offset from the source opposite to the first point.

10. The multi-level multileaf collimator of claim 9 , wherein

wherein a first lateral side of a beam-blocking leaf of the second type is adjacent to a second lateral side of a beam-blocking leaf of the first type, and a second lateral side of a beam-blocking leaf of the second type is adjacent to a first lateral side of a beam-blocking leaf of the first type, and

first lateral sides of the plurality of beam-blocking leaves of the second type align to converge to the second point, and second lateral sides of the plurality of beam-blocking leaves of the second type align to converge to the first point.

11. The multi-level multileaf collimator of claim 10 , wherein the first point offsets from the source at a distance substantially equal to a distance that the second point offsets from the source.

12. The multi-level multileaf collimator of claim 8 , wherein a first lateral side and a second lateral side of each of the plurality of beam-blocking leaves of the first type, and a first lateral side and a second lateral side of each of the plurality of beam-blocking leaves of the second type are substantially flat.

13. The multi-level multileaf collimator of claim 8 , wherein the first MLC comprises a plurality of beam-blocking leaves, each being longitudinally movable in a direction substantially parallel with the longitudinal moving direction of the plurality of beam-blocking leaves of the first type and the plurality of beam-blocking leaves of the second type of the second MLC.

14. The multi-level multileaf collimator of claim 13 , wherein each of the plurality of beam-blocking leaves of the first type and the plurality of beam-blocking leaves of the second type of the second MLC laterally offsets a beam-blocking leaf of the first MLC.

15. An apparatus, comprising:

a source of radiation, and

a multileaf collimator comprising:

a plurality of beam-blocking leaves of a first type, each of the plurality of beam-blocking leaves of the first type having a trapezoidal geometry viewed in a longitudinal moving direction with a first lateral side, a second lateral side, a wider end, and a narrower end, the wider end being proximal the source of radiation;

a plurality of beam-blocking leaves of a second type, each of the plurality of beam-blocking leaves of the second type having a trapezoidal geometry viewed in the longitudinal moving direction with a first lateral side, a second lateral side, a wider end, and a narrower end, the wider end being distal to the source of radiation; and

the plurality of beam-blocking leaves of the first type being alternatingly arranged with the plurality of beam-blocking leaves of the second type side by side.

16. The apparatus of claim 15 , wherein the source of radiation comprises a source of x-rays, a source of gamma rays, a source of protons, or a source of heavy ions.

17. The apparatus of claim 15 , wherein the multileaf collimator comprises a first multileaf collimator in a first level distal to the source of radiation and a second multileaf collimator in a second level proximal to the source of radiation, wherein the plurality of beam-blocking leaves of the first type and the plurality of beam-blocking leaves of the second type are arranged in the second multileaf collimator.

18. The apparatus of claim 17 , wherein the first multileaf collimator comprises a plurality of beam-blocking leaves, and each of the plurality of beam-blocking leaves of the first type and the plurality of beam-blocking leaves of the second type of the second multileaf collimator laterally offsets one of the plurality of beam-blocking leaves of the first multileaf collimator.

19. The apparatus of claim 15 , wherein

first lateral sides of the plurality of beam-blocking leaves of the first type align to converge to a first point offset from the source, and

second lateral sides of the plurality of beam-blocking leaves of the first type align to converge to a second point offset from the source opposite to the first point.

20. The apparatus of claim 19 , wherein

a first lateral side of a beam-blocking leaf of the second type is adjacent to a second lateral side of a beam-blocking leaf of the first type, and a second lateral side of a beam-blocking leaf of the second type is adjacent to a first lateral side of a beam-blocking leaf of the first type, and

first lateral sides of the plurality of beam-blocking leaves of the second type align to converge to the second point, and second lateral sides of the plurality of beam-blocking leaves of the second type align to converge to the first point.