We claim:
1. A method of detecting bandwidth capabilities over a network, comprising detecting bandwidth in stages depending upon comparing a conducted detection measurement against resolution limitations.
2. The method of claim 1, comprising:
conducting a first bandwidth measurement employing a small package download;
determining whether the first measured bandwidth is within resolution limitations; and
if the first measured bandwidth is determined to be outside resolution limitations, then conducting a second bandwidth measurement employing a larger package download.
3. The method of claim 2, wherein the small package download is selected to be conducted within no more than about four seconds using the slowest expected communication mechanism.
4. The method of claim 3, wherein the larger package download is selected to take no more than about three seconds using a commonly employed network equipment one increment faster than the slowest expected communication mechanism.
5. The method of claim 2, wherein the first bandwidth measurement comprises downloading a small package, timing the small package download, and first calculating the bandwidth based on the timed small package download.
6. The method of claim 5, wherein determining whether the first measured bandwidth is within resolution limitations comprises determining whether the timed small package download is within timer resolution.
7. The method of claim 5, wherein the second bandwidth measurement comprises:
downloading a larger package;
timing the larger package download; and
second calculating the bandwidth from the timed larger package download.
8. The method of claim 7, further comprising:
determining the small package size prior to first calculating; and
determining the larger package size prior to second calculating.
9. The method of claim 2, further comprising:
determining whether the second measured bandwidth is within the resolutions limitations; and
recalculating bandwidth by downloading a package larger than the larger package.
10. The method of claim 9, further comprising continually recalculating bandwidth using progressively larger package downloads until the calculated bandwidth is within the resolution limitations.
11. A method of optimizing streaming video across a network, comprising:
detecting bandwidth capabilities at a terminal on the network; and
adjusting a display frame size based upon the detected bandwidth.
12. The method of claim 11, wherein detecting bandwidth capabilities comprises conducting a staged bandwidth measurement using progressively larger package downloads until the measured bandwidth is within system resolution limitations.
13. The method of claim 12, wherein the system resolution limitations comprise timer limitations.
14. The method of claim 11, wherein detecting bandwidth capabilities is initiated prior to user initiation of displaying the streaming video.
15. The method of claim 11, wherein detecting bandwidth capabilities is conducted continually during presentation to determine whether detected bandwidth remains within defined configurable thresholds for a currently employed presentation media.
16. A generalized system for delivering streaming data to a client on a network, the system including a detection mechanism configured to automatically select from a plurality of available information streams for a given presentation.
17. The system of claim 16, wherein a detection mechanism is configured to repeatedly measure bandwidth and determine bandwidth measurement accuracy until the measured bandwidth is within system resolution limitations.
18. The system of claim 17, wherein the repeated bandwidth measurements download progressively larger packages and measure elapsed time during the downloads.
19. The system of claim 16, wherein the detection mechanism employs a static presentation if a measured bandwidth is too low to support a rich media presentation.
20. The system of claim 16, configured to initiate bandwidth detection prior to user selection to display the given presentation.
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 irradiating a target with a beam of energetic radiation formed by electrically charged particles, comprising the steps of
providing a pattern definition means having a plurality of apertures transparent to said radiation,
illuminating said pattern definition means by means of an illuminating wide beam, which traverses the pattern definition means through said apertures thus forming a patterned beam consisting of a corresponding plurality of beamlets,
forming said patterned beam into a pattern image on the location of the target, said pattern image comprising the images of at least part of the plurality of apertures covering a number of pattern pixels on the target, and
generating a relative movement between said target and the pattern definition means producing a movement of said pattern image on the target along a path over a region where a beam exposure is to be performed, said region being composed of a plurality of pattern pixels arranged in a regular arrangement and having a total width as measured across a main direction of said relative movement, said movement defining a number of stripes covering said region in sequential exposures, said stripes running substantially parallel to each other along said main direction and having respective widths as measured across said main direction,
wherein the number of stripes is written in a consecutive order in at least two passes, wherein each stripe belongs to exactly one of said passes,
wherein for each pass, the widths of the stripes of one pass combine into a cover of the total width,
wherein each pass is associated with one of a number of partial grids of pattern pixels which are exposable during the respective pass, the partial grids being mutually different and, when taken together, combining to the complete plurality of pattern pixels which compose said region where a beam exposure is to be performed.
2. The method of claim 1, wherein the stripes of each pass are distributed into at least two groups of spatially adjacent stripes, and the stripes are written either in a time sequence wherein either each stripe is followed by a non-adjacent stripe of a different group, or in a time sequence wherein the stripes are written in groups of stripes according to the order of the groups, with each group of stripes being followed by a non-adjacent different group.
3. The method of claim 2, wherein the passes are written in a temporally interlacing order, by writing groups of at least two stripes belonging to a respective one of the passes in immediate consecutive order, and groups of stripes are written for alternating passes.
4. The method of claim 3, wherein groups of stripes covering substantially the same area on the target are written in immediate consecutive order.
5. The method of claim 1, wherein groups of stripes belonging to the same pass are written subsequently in time.
6. The method of claim 1, wherein the stripes are located such that for each stripe, a boundary of said stripe having an orientation parallel to said main direction falls within a central region of a stripe of a different pass.
7. The method of claim 1, wherein the stripes of each pass have uniform width, the stripes of different passes being offset to each other by an offset value which is substantially equal to an integer multiple of the width plus a fraction of the width, said fraction corresponding to the inverse of the number of passes.
8. The method of claim 1, wherein within each pass consecutive stripes are exposed at lateral offsets to each other which correspond to the respective widths of the stripes.
9. The method of claim 1, wherein the stripes of at least one of the passes are overlapping, wherein in the range of overlap of two stripes of the same pass:
nominal positions of pattern pixels of one of the two stripes are overlapping with nominal positions of corresponding pattern pixels of the other of the two stripes, and
pattern pixels are exposed in the two overlapping stripes in a complementary manner with regard to the pattern to be imposed.
10. The method of claim 1, wherein within each stripe, the pattern pixels are selectively exposed according to an actual pattern to be exposed, wherein through pixels of different partials grids different pixel locations of the actual pattern are exposable.
11. The method of claim 10, wherein the total width is divided into a number of regions, and for each region, depending on a comparison between a pattern pixel density evaluated based on the actual pattern within the respective region and a predetermined threshold value andor a comparison between the number of groups per pass in the respective region and a predetermined constant, a decision is made for the time sequence of writing the stripes, namely, between a time sequence wherein each stripe is followed by a non-adjacent stripe of a different group, and a time sequence wherein the stripes are written in groups of stripes according to the order of the group, with each group of stripes being followed by a non-adjacent different group.
12. The method of claim 10, wherein the total width is divided into a number of regions, and for each region, depending on a comparison between a pattern pixel density evaluated based on the actual pattern within the respective region and a predetermined threshold value andor a comparison between the number of groups per pass in the respective region and a predetermined constant, a decision is made for the time sequence of writing the stripes, namely, between a time sequence wherein the stripes of each pass are written in immediate consecutive order, and a time sequence wherein either each stripe is followed by a non-adjacent stripe of a different group, or wherein the stripes are written in groups of stripes according to the order of the group, with each group of stripes being followed by a non-adjacent different group.
13. The method of claim 1, wherein during the uniformly timed exposure steps, during which respective pattern pixels are exposed on the target, the location of the pattern image is moved along with the target at least with respect to the relative movement along the main direction, and between exposure steps the location of the pattern image is changed with respect to the target, generally compensating the movement of the location of the pattern image with regard to the location of the pattern definition means, wherein the duration of said exposure steps corresponds to a uniform distance of advance along the main direction, said distance of advance being greater than the size of an aperture image within the same partial grid along the main direction.
14. The method of claim 1, wherein the positions of the images of apertures on the target are arranged according to a two-dimensional regular arrangement defined in the pattern definition mean.
15. The method of claim 1, wherein the partial grids are mutually disjoint with regard to nominal positions of images of apertures which define pattern pixels.
16. The method of claim 1, wherein the partial grids have a pitch being equal or smaller than the width of the images of apertures on the target.
17. The method of claim 16, wherein the regular partial grids are placement grids employing oversampling with an oversampling factor o>1.
18. The method of claim 16, wherein the pitch is equal to the width of the images of apertures on the target times \xbdke, with ke being a positive integer.