High speed scanning system with acceleration tracking

1. An optical scanning system for imaging a moving substrate, comprising:

a. a stage, said stage capable of moving along an axis, said stage configured to hold a substrate comprising a plurality of fields;

b. an objective lens;

c. a camera capable of acquiring an image of one of said plurality of fields through the objective lens, said image acquired via an optical path defined from one of said plurality of fields through said objective lens to said camera during acquisition of said image;

d. a velocity tracking mirror mounted along said optical path;

e. a first electrical motor operably coupled to said velocity tracking mirror to adjust the angle of the tracking mirror along said axis of stage movement in said optical path;

f. a controller module operably coupled to said first electrical motor to send a first driving signal to said first electrical motor, wherein said first driving signal is a function of a velocity measurement of the stage movement along said axis;

g. an acceleration tracking mirror mounted along said optical path, wherein a movement of said velocity tracking mirror and said acceleration tracking mirror reduce a tracking error of said plurality of fields by said camera as compared to without a movement of said acceleration tracking mirror; and

h. a second electrical motor operably coupled to said acceleration tracking mirror to adjust the angle of the acceleration tracking mirror along said axis of stage movement in said optical path, wherein said controller module is operably coupled to said second electrical motor to send a second driving signal to said second electrical motor, wherein said second driving signal is a function of the change of the stage velocity along said axis.

2. The system of claim 1 , wherein the tracking error is reduced to less than 0.1%.

3. The system of claim 1 , wherein the tracking error is reduced to less than 1 pixel.

4. A method of imaging a plurality of fields on a moving substrate, comprising

a. providing an optical scanning system comprising:

i. a moveable stage holding a substrate comprising a plurality of fields,

ii. a camera,

iii. an objective lens,

iv. a velocity tracking mirror, and

v. an acceleration tracking mirror, wherein a movement of said velocity tracking mirror and said acceleration tracking mirror reduce a tracking error of said plurality of fields by said camera as compared to without a movement of said acceleration tracking mirror;

b. moving said moveable stage along an axis, thereby moving said substrate comprising a plurality of fields along said axis; and

c. concurrent with said movement, capturing an image of one of said plurality of fields passing through said objective lens using said camera, wherein said image of said field is stabilized during said image capture by:

i. rotating said velocity tracking mirror as a function of a velocity of the moveable stage along said axis, and

ii. rotating said acceleration tracking mirror as a function of a change in the velocity of the moveable stage along said axis.

5. The method of claim 4 , wherein the tracking error is reduced to less than 0.1%.

6. The method of claim 4 , wherein the tracking error is reduced to less than 1 pixel.

7. A method of imaging a plurality of fields on a moving substrate, comprising

a. providing an optical scanning system comprising:

i. a moveable stage holding a substrate comprising a plurality of fields,

ii. a camera,

iii. an objective lens,

iv. a velocity tracking mirror, and

v. an acceleration tracking mirror;

b. moving said moveable stage along an axis, thereby moving said substrate comprising a plurality of fields along said axis;

c. concurrent with said movement, capturing an image of one of said plurality of fields passing through said objective lens using said camera, wherein said image of said field is stabilized during said image capture by:

i. rotating said velocity tracking mirror as a function of a velocity of the moveable stage along said axis, and

ii. rotating said acceleration tracking mirror as a function of a change in the velocity of the moveable stage along said axis; and

d. a second velocity tracking mirror and a second acceleration tracking mirror, further comprising, concurrent with said movement of said moveable stage and said image capture of one of said plurality of fields:

i. rotating said second velocity tracking mirror as a function of a velocity of the moveable stage along a second axis, and

ii. rotating said second acceleration tracking mirror as a function of a velocity fluctuation of the moveable stage along said second axis thereby stabilizing imaging of said field for at least two axes simultaneously.

8. A method of imaging a plurality of fields on a moving substrate, comprising

a. providing an optical scanning system comprising:

i. a moveable stage holding a substrate comprising a plurality of fields,

ii. an objective lens,

iii. a camera,

iv. a motion tracking mirror, and

v. an electric motor operatively coupled to said motion tracking mirror to effect movement of said motion tracking mirror to track said movement of said moveable stage along said axis during an image capture, and to return said motion tracking mirror to an initial position after said image capture;

b. moving said moveable stage along an axis, thereby moving said substrate comprising a plurality of fields along said axis; and

c. generating an image for each of M fields of said substrate, comprising performing at least M image capture cycles during movement of said moveable stage along said axis, each cycle comprising:

i. providing a cycle M driving signal to an electric motor to control movement of said tracking mirror to track the velocity of said moveable stage along said axis;

ii. capturing an image of said field while said tracking mirror is tracking said moving stage; and

iii. determining an average velocity of said field, wherein said average velocity is used to generate a cycle M+1 driving signal to control movement of said electric motor during cycle M+1.