1. An imaging system comprising:
an image source providing an image having a resolution of X by Y pixels where X and Y are integers; and
a digital mirror device including an array of mirror elements, each mirror element having a generally diamond shape, wherein the array includes fewer than X*Y mirror elements;
a display memory coupled to the digital mirror device; and
a processor coupled to the display memory.
2. The system of claim 1 wherein the array includes X*Y2 mirror elements.
3. The system of claim 2 wherein the array includes at least 460,800 mirror elements.
4. The system of claim 2 wherein the array includes at least 1,036,800 mirror elements.
5. The system of claim 1 wherein the image source comprises a video source.
6. The system of claim 5 wherein the image source comprises a source of high definition television.
7. The system of claim 1 wherein each mirror element comprises a square.
8. The system of claim 7 wherein the array of mirror elements comprises rows and columns of mirror elements, and wherein each mirror element is arranged so that an edge is rotated approximately 45\xb0 relative to a line running through one of the rows or columns.
9. The system of claim 1 wherein the processor includes a pre-filter, the pre-filter receiving image data from the image source.
10. The system of claim 9 wherein the pre-filter comprises a 5\xd75 pre-filter.
11. The system of claim 10 wherein the pre-filter comprises a thirteen-tap filter with tap weightings determined by:
0
–
23
0
–
23
0
–
23
0
68
0
–
23
0
68
168
68
0
–
23
0
68
0
–
23
0
–
23
0
–
23
0
\xd7
1
256
.
12. An imaging system comprising:
a image source providing an image having a resolution of X by Y pixels where X and Y are integers; and
a digital mirror device including an array of mirror elements, having a generally diamond shape, wherein the array includes fewer than X*Y mirror elements;
a display memory coupled to the digital mirror device; and
a processor coupled to the display memory, wherein the image source comprises a source of analog image data, the imaging system further comprising an analog-to-digital converter coupled between the image source and the digital mirror device.
13. The system of claim 12 wherein the image includes a plurality of lines of image data, and wherein the analog-to-digital converter includes a control input operable to receive a timing signal to determine sampling points, wherein the timing signal shifts the sampling point for every other line of image data.
14. The system of claim 13 and further comprising a timing circuit with an output coupled to the control input of the analog-to-digital converter.
15. The system of claim 14 wherein the timing signal further includes a component to compensate for jitter.
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. Silicon-based photovoltaic cell wherein the silicon comprises a concentration of donor dopant elements andor of acceptor dopant elements larger than or equal to 5 ppma, the difference between these two concentrations being less than or equal to 5 ppma.
2. Photovoltaic cell according to claim 1, wherein the boron concentration is larger than or equal to 5 ppma.
3. Photovoltaic cell according to claim 1, wherein the phosphorus concentration is larger than or equal to 5 ppma.
4. Method for producing photovoltaic grade crystalline silicon by crystallization of a molten silicon feedstock, method wherein the sum of the initial concentrations of donor dopant elements and acceptor dopant elements in the silicon feedstock is larger than 0.1 ppma, both the acceptor and donor dopant element concentrations being lower than 25 ppma, the method comprises before crystallization of the silicon:
determining the concentrations of donor-type and acceptor-type doping material initially present in the feedstock,
adding at least a predefined quantity of a doping material having a segregation coefficient of less than 0.1 so as to comply, over at least 50% of the crystallized silicon from the beginning of crystallization, either with a first equation for a P-type crystalline silicon
0.1 ppma\u2266\u03a3kaC0a(1\u2212x)kd-1\u2212\u03a3kdC0d(1\u2212x)kd-1\u22665 ppma
or with a second equation for an N-type crystalline silicon
0.1 ppma\u2266\u03a3kdC0d(1\u2212x)kd-1\u2212\u03a3kaC0a(1\u2212x)ka-1\u22665 ppma,
equations in which
ka, kd correspond to the segregation coefficients respectively of the acceptor dopant elements and of the donor dopant elements,
C0a, C0d correspond respectively to the concentrations of acceptor dopant elements and of donor dopant elements in the molten silicon just before crystallization,
x corresponds to the fraction of crystallized silicon.
5. Method according to claim 4, wherein the doping material having a segregation coefficient of less than 0.1 is chosen from gallium, antimony, indium and bismuth.
6. Method according to claim 4, comprising addition of boron, phosphorus, arsenic, aluminium andor tin before crystallization to satisfy the equation corresponding to the type of crystalline silicon produced.
7. Method according to claim 4, wherein the sum of the initial concentrations of donor doping elements dopants and of acceptor doping elements is larger than 5 ppma.
8. Method according to claim 7, wherein the boron concentration being comprised between 5 and 20 ppma, the crystalline silicon obtained is of P type.
9. Method according to claim 7, wherein the boron concentration being comprised between 5 and 15 ppma, the crystalline silicon obtained is of N type.