1. A solid-state semiconductor light emitting device comprising:
a heat sink having a receiving cup that projects from a center of said heat sink for receiving a chip; and
a leadframe, in which two holders having two top sides on two top portions thereof are opposite to one another and a holder having holes is mounted between said two top sides, wherein said holder having said holes is connected to one of said two opposite holders, and a plastic material is applied to mold said three holders into a connection base for receiving said receiving cup of said heat sink;
thereby said chip is connected to said leadframe via a metal wire and a resin or silicone are applied to cover all of them so as to form said solid-state semiconductor light emitting device that has good heat-dissipating efficacy and can enhance connection stability.
2. The solid-state semiconductor light emitting device of claim 1, wherein a plurality of through holes are mounted on said connection base for exposing said three holders.
3. The solid-state semiconductor light emitting device of claim 1, wherein a protrusion is mounted on said bottom surface of said heat sink.
4. The solid-state semiconductor light emitting device of claim 3, wherein said protrusion is in the form of radiation.
5. The solid-state semiconductor light emitting device of claim 3, wherein said protrusion is arranged in the form of homocentric circles.
6. The solid-state semiconductor light emitting device of claim 1, wherein said holder having said holes is connected to one of said two opposite holders in a random position.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A method for automatically determining the best effective reconstruction gap in a CT apparatus, wherein the CT apparatus comprises a detector comprising a plurality of modules with physical gaps between the plurality of modules, the method comprising:
scanning a phantom to collect image data of the phantom;
obtaining a plurality of images by using a plurality of different gap values to reconstruct image of the phantom, wherein each of the plurality of images is respectively associated with a gap value of the different gap values;
selecting the best image from the plurality of images; and
automatically determining the gap value associated with the best image, and saving the determined gap value as the best effective reconstruction gap.
2. The method according to claim 1, wherein selecting the best image from the plurality of images comprises manually selecting the best image by a user based on visual evaluation of a band artifact in each of the plurality of images.
3. The method according to claim 1, wherein selecting the best image from the plurality of images comprises automatically selecting the best image by the CT apparatus based on calculation of a band artifact parameter in each of the plurality of images.
4. The method according to claim 3, wherein the calculation of the band artifact parameter in each of the plurality of images comprises:
estimating a location and a width of the band artifact in the image based on the location and the size of the physical gap, and based on the geometry of the CT apparatus;
determining locations of a band artifact region of interest, a first neighbor region of interest, and a second neighbor region of interest based on the estimated location and the estimated width of the band artifact;
averaging CT values of all pixels within the first neighboring region of interest and the second neighboring region of interest to obtain a background CT value;
averaging CT values of all pixels within the band artifact region of interest to obtain a band artifact CT value; and
calculating an absolute value of a difference between the background CT value and the band artifact CT value to obtain the band artifact parameter.
5. The method according to claim 3, wherein the calculation of the band artifact parameter in each of the plurality of images comprises:
estimating a location and a width of the band artifact in the image based on the location and the size of the physical gap and based on the geometry of the CT apparatus;
determining locations of a band artifact region of interest, a first neighbor region of interest, and a second neighbor region of interest based on the estimated location and the estimated width of the band artifact;
averaging CT values of all pixels within the first neighbor region of interest and the second neighbor region of interest to obtain a background CT value;
sorting CT values of all pixels within the band artifact of interest in descending order as 1st pixel up to Nth pixel, where N is the total number of pixels within the band artifact region of interest;
averaging the CT values of all pixels within the band artifact region of interest to obtain a band artifact region of interest CT value;
comparing the background CT value and the band artifact region of interest CT value;
determining that the band artifact parameter is equal to zero if the background CT value is equal to the band artifact region of interest CT value, and comparing the background CT value with the 1st pixel and the Nth pixel if the background CT value is not equal to the band artifact region of interest CT value;
determining the band artifact region of interest CT value as a band artifact CT value if a condition that the background CT value is larger than the 1st pixel or is less than the Nth pixel is satisfied, or if the condition is not satisfied, sequentially fetching M pixels, starting from the Nth pixel if the background CT value is less than the band artifact region of interest CT value, or sequentially fetching M pixel, starting from the 1st pixel if the background CT value is larger than the band artifact region of interest CT value, until a mean value of CT values of the M pixels is equal to the background CT value, where 1\u2266M<N, and then calculating a mean value of CT values of remaining (N\u2212M) pixels within the band artifact region of interest as the band artifact CT value; and
calculating an absolute value of a difference between the background CT value and the band artifact CT value to obtain the band artifact parameter.
6. The method according to claim 4, wherein the location of the physical gap is calculated based on serial numbers of detecting channels in the detector, while the size of the physical gap is actually measured.
7. The method according to claim 1, wherein the phantom is a water phantom.
8. The method according to claim 7, wherein the water phantom is small in size and is arranged in an off-centered manner.
9. The method according to claim 7, wherein the water phantom is small in size and is centrally arranged to cover only the physical gap of a center module in the detector.
10. The method according to claim 7, wherein the water phantom is large in size, and a large current of an X-ray source and a large slice thickness is employed when the water phantom is scanned.
11. The method according to claim 1, wherein the plurality of different gap values are entered manually by a user or set automatically by the CT apparatus.
12. The method according to claim 1, wherein a standard kernel function andor a sharp kernel function is employed during reconstructing an image of the phantom.
13. The method according to claim 12, wherein the sharp kernel function is a bone kernel function or an edge kernel function.
14. A method for removing a band artifact in a reconstructed image in a CT apparatus, the method comprising:
scanning an object to collect image data of an object;
reconstructing an image of the object based on the image data of the object by using the best effective reconstruction gap determined by the method according to claim 1.
15. A method for determining a band artifact parameter in a reconstructed image in a CT apparatus, comprising:
estimating location and width of a band artifact in an image based on location and size of individual physical gaps between a plurality of modules in a detector of the CT apparatus;
determining locations of a band artifact region of interest, a first neighbor region of interest and a second neighbor region of interest based on the estimated location and width of the band artifact;
averaging CT values of all pixels within the first neighbor region of interest and the second neighbor region of interest to obtain a background CT value;
sorting CT values of all pixels within the band artifact region of interest in descending order as 1st pixel up to Nth pixel, where N is the total number of pixels within the band artifact region of interest;
averaging the CT values of all pixels within the band artifact region of interest to obtain a band artifact region of interest CT value;
comparing the background CT value and the band artifact region of interest CT value;
determining that the band artifact parameter is equal to zero if the background CT value is equal to the band artifact region of interest CT value, and comparing the background CT value with the 1st pixel and the Nth pixel if the background CT value is not equal to the band artifact region of interest CT value;
determining the band artifact region of interest CT value as a band artifact CT value if a condition that the background CT value is larger than the 1st pixel or is less than the Nth pixel is satisfied, or if the condition is not satisfied, sequentially fetching M pixels, starting from the Nth pixel if the background CT value is less than the band artifact region of interest CT value, or sequentially fetching M pixel, starting from the 1st pixel if the background CT value is larger than the band artifact region of interest CT value, until a mean value of CT values of the M pixels is equal to the background CT value, where 1\u2266M<N, and then calculating a mean value of CT values of remaining (N\u2212M) pixels within the band artifact region of interest as the band artifact CT value; and
calculating an absolute value of a difference between the background CT value and the band artifact CT value to obtain the band artifact parameter.
16. The method according to claim 15, wherein the location of the physical gap is calculated based on serial numbers of detecting channels in the detector, while the size of the physical gap is actually measured.
17. A CT apparatus, comprising:
an X-ray source;
a collimator;
a detector comprising a plurality of modules with physical gaps between the plurality of modules;
a processor configured to determine the best effective reconstruction gap by processing a plurality of images, wherein each of the plurality of images is respectively associated with a gap value, receiving a selection of the best image from the plurality of images, and determining the gap value associated with the best image as the best effective reconstruction gap; and
an image reconstructor configured to reconstruct an image of a scanned object by using the best effective reconstruction gap.
18. The CT apparatus according to claim 17, wherein the plurality of modules in the detector are flat modules.