Alternative detector configuration and mode of operation of a time delay integration particle analyzer

A method for determining at least one characteristic of an object, comprising the steps of:

• (a) directing light from the object onto a generally planar surface of a time delay integration (TDI) detector to form an image of the object, said generally planar surface being inclined relative to an axis along which the light from the object is directed onto the TDI detector, said TDI detector producing an output signal corresponding to the image of the object at least at one point along an inclined focal plane that passes through the object, said inclined focal plane being inclined relative to the planar surface of the TDI detector so that the inclined focal plane intersects the object at different focal points within the object over time;
• and
• (b) reading the output signal from the TDI detector, said output signal being indicative of said at least one characteristic of the object at said at least one focal point within the object.

A system for obtaining an output signal corresponding to an image of an object and indicative of at least one characteristic of the object, wherein there is relative motion between the object and the system, comprising:

• (a) a time delay integration (TDI) detector disposed to receive light from the object along an imaging path, a plane of said TDI detector being inclined at a non-orthogonal angle relative to the imaging path and inclined relative to a direction of the relative motion, said TDI detector producing an output signal that propagates over the TDI detector and corresponds to the image of the object formed on the TDI detector at least at one focal point along an inclined focal plane that passes through the object;
• and
• (b) an optical element disposed between the object and the TDI detector and oriented so that light traveling from the object is directed along the imaging path onto the plane of the TDI detector, forming the image of the object on the TDI detector, said output signal from the TDI detector being indicative of said at least one characteristic of the object at said at least one focal point within the object.