What is claimed is:
1. An image processing apparatus comprising:
a sensor including a plurality of pixels each including a light receiving element, and a scanning circuit for reading out signals in time sequence from the plurality of pixels; and
a drive circuit which supplies pulses for driving said scanning circuit,
wherein said drive circuit is so arranged to output at least a first pulse and a second pulse smaller than the first pulse, and said drive circuit supplies the first pulse to said scanning circuit when a first resolution is selected, and supplies the first pulse and the second pulse to said scanning circuit when a second resolution lower than the first resolution is selected.
2. An apparatus according to claim 1, wherein when the second resolution is selected, said drive circuit supplies the first pulse in every other pulse or in every plurality of pulses.
3. An apparatus according to claim 2, further comprising a signal processing circuit which performs image processing on the basis of signals which are read out by supplying the first pulse to said scanning circuit.
4. An apparatus according to claim 2, wherein said sensor is formed on the same semiconductor chip, and a plurality of said sensors are mounted on a mount board.
5. An apparatus according to claim 1, wherein each of said pixels has an amplifying device which amplifies a signal from the light receiving element, and which outputs the amplified signal, a reset switch for resetting an input portion of said amplifying device, and a selecting switch for selectively reading the signal from said amplifying device, said selecting switch being supplied with a pulse from said scanning circuit.
6. An apparatus according to claim 1, further comprising a control circuit for switching between the first resolution and the second resolution.
7. An apparatus according to claim 1, further comprising a light source for irradiating light on said sensor, and a transport member for moving an original and said sensor relative to each other.
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 of determining the offset of the head part of an orthopaedic joint prosthesis stem component; relative to the neck of the stem part on which the head part can be fitted for an implantation procedure involving a patient’s joint, comprising the steps of:
obtaining a first image of the patient’s joint on a first plane;
obtaining a second image of the patient’s joint on a second plane, wherein the planes are non-coincident and in which the angle between the planes is known;
fitting a template part having a scale and markings thereon to the first image of the bone relative to the head part and the stem part to measure the first displacement which is defined as the distance between the axis of the head part and the axis of the neck of the patient’s bone measured in the first plane;
fitting a template part having a scale and markings thereon to the second image of the bone relative to the head part and the stem part to measure the second displacement which is defined as the distance between the axis of the head part and the axis of the neck of the patient’s bone measured in the second plane;
determining, by using reference data to calculate from the first and second displacements, the r,\u03b8 coordinates of the axis of the head part relative to the axis of the neck of the stem part, where r is the absolute distance between the axis of the head part and the axis of the neck of the stem part, and \u03b8 is a measure of the angular location of the axis of the head part around the axis of the neck of the stem part.
2. The method of claim 1, wherein the angle between the first and second planes is at least about 80 degrees.
3. The method of claim 1, wherein the angle between the first and second planes is not more than about 100 degrees.
4. The method of claim 1, wherein the angle between the first and second planes is about 90 degrees.
5. The method of claim 1, wherein the first image is created in the plane that is perpendicular to the anterior-posterior axis.
6. The method of claim 1, wherein the second image is created in the plane that is perpendicular to the medial-lateral axis.
7. The method of claim 1, wherein the reference data are provided in a printed chart.
8. The method of claim 1, wherein a common template part is fitted to the first and second images of the bone.
9. The method of claim 1, wherein at least one of the fitting steps includes a step of fitting a stem template part to at least one of the first and second images of the bone for use in locating the axis of the neck of the stem part.
10. The method of claim 9, wherein the stem template part has printed thereon an outline of a stem part of the joint prosthesis component.
11. The method of claim 1, further comprising the step of assembling a head part and a stem part, wherein the distance between the axis of the head part and the axis of the neck of the stem part, and the angular location of the axis of the head part around the axis of the neck component, are as determined in the determining step.
12. The method of claim 1, wherein the steps of obtaining images comprises obtaining the images using an X-ray imaging technique.
13. The method of claim 1, further comprising the steps of: aligning a head part and a stem part of an orthopaedic joint component according to the coordinates which are determined in the determining step; and connecting the head part to the stem part.
14. The method of claim 13, wherein the head part and the stem part are parts of a trial instrument.
15. The method of claim 13, wherein the head part and the stem part are parts of a joint prosthesis.
16. The method of claim 13, wherein the orthopaedic joint prosthesis comprises a connector for connecting the head part to a stem part, wherein the head part has an eccentric recess therein for receiving the connector, and the connector has an eccentric connection feature for connection to the stem part.
17. The method of claim 13, wherein an alignment guide is used in the aligning step, the aligning guide having a recess formed therein, the recess configured to accept the neck of the stem part, and markings thereon by which the angular location of the axis of the head part around the axis of the neck of the stem part can be estimated.
18. The method of claim 17, wherein the alignment guide has a marking thereon that provides a point of reference relative to a feature on the stem part or on a bone of the patient’s joint.
19. A template kit for use in a method of determining the offset of the head part of an orthopaedic joint prosthesis stem component, relative to the neck of the stem part on which the head part can be fitted for an implantation procedure involving a patient’s joint, comprising:
a first template part having markings thereon that represent the axis of the head of the patient’s bone,
a second template part having markings thereon that represent the axis of the neck of the patient’s bone,
a scale that is provided on at least one of the first and second template parts for use when measuring the distance between the axis of the head part and the axis of the neck of the patient’s bone,
a source of reference data that can provide, based on two such measured distances, the r,\u03b8 coordinates of the axis of the head part relative to the axis of the neck of the stem part, where r is the absolute distance between the axis of the head part and the axis of the neck of the stem part, and \u03b8 is a measure of the angular location of the axis of the head part around the axis of the neck of the stem part.
20. The kit of claim 19, wherein at least one of the first template part and the second template part includes a representation of the cup component of the joint prosthesis with which the head part of the stem component articulates.
21. The kit of claim 19, wherein the reference data are provided in a printed chart.
22. A method of assembling a joint prosthesis component, which comprises:
obtaining a first image of the patient’s joint on a first plane,
fitting a template part to the first image of the bone, wherein the template part has markings thereon that can be placed relative to the head part and the stem part respectively of the patient’s bone, and a scale thereon for use when measuring the first displacement defined as the distance between the axis of the head part and the axis of the neck of the patient’s bone measured in the first plane,
providing a head part of a joint prosthesis and a connector for connecting the head part to a stem part, wherein the head part has an eccentric recess therein for receiving the connector, and the connector has an eccentric connection feature for connection to the stem part, and
locating the connector in the recess in the head part, and aligning it to provide a desired offset with reference to the displacement measurement obtained in step (a).
23. The method of claim 22, wherein the head part and the connector are parts of a trial prosthesis instrument.
24. The method of claim 22, wherein the head part and the connector are parts of a prosthesis component implant.