Image projection method and apparatus for supporting manual MALDI sample preparation
An improved deposition aid for manual sample preparation, particularly on flat MALDI sample supports, comprises a holder for a sample support with several sample sites, which is adapted to standardized sample supports for ionization with matrix-assisted laser desorption and a device which projects a two-dimensional optical image, or a suitable sequence of images, onto the sample sites. The image, or sequence of images, is constructed such that a selected sample site or group of selected sample sites is highlighted in a way which can be perceived by the human eye, at least with respect to neighboring, not-selected sample sites. The deposition aid also includes an interface for confirming the manual deposition and/or a device for the automatic detection of a manual deposition process; and a guidance system which selects a sample site or group of sample sites, and controls the device accordingly.
1. A deposition aid for manual preparation of samples on a sample support for subsequent ionization via matrix-assisted laser desorption, the aid comprising:
a base plate containing a holder for a sample support which has several sample sites;
a microprocessor or equivalent thereof, which selects one of the several sample sites, based on configuration data of the sample sites on the sample support;
a vertical support located at one side of the base plate;
a video projector mounted on the vertical support that communicates with and is controlled by the microprocessor or equivalent thereof and projects onto at least a portion of the sample sites, at a non-orthogonal angle relative to a plane of the sample support, at least one two-dimensional optical image that is constructed so that the selected sample site is highlighted with respect to neighboring, not-selected sample sites in a manner which can be perceived by the human eye; and
optics, including at least one of a lens and a mirror, that condition the image to be displayed substantially without distortion.
2. The deposition aid of claim 1 wherein the projector projects a sequence of images onto the sample sites.
3. The deposition aid of claim 1 , wherein the projector comprises one of a spatial light modulator, a liquid crystal projector and a liquid-crystal-on-silicon projector.
4. The deposition aid of claim 1 , wherein the projector generates the at least one image with at least one of a brightness contrast and a color contrast at the selected sample site in order to highlight the selected sample site.
5. The deposition aid of claim 1 , wherein the projector generates a sequence of images which highlights a group of sample sites with respect to neighboring, not-selected sample sites in a manner which can be perceived by the human eye.
6. The deposition aid of claim 1 , wherein the at least one two-dimensional optical image is sized to cover all of the sample sites simultaneously.
7. The deposition aid of claim 1 , wherein the microprocessor or equivalent thereof has an electrical interface for one of data input and data output.
8. The deposition aid of claim 1 , wherein the microprocessor or equivalent thereof has a memory for the assignment and acquisition of identification tags of samples and sample sites.
9. The deposition aid of claim 1 , further comprising adapter pieces which can be placed in the holder so that standardized sample supports for ionization via matrix-assisted laser desorption fit tightly into the holder.
10. The deposition aid of claim 1 , wherein the at least one two-dimensional image includes an area which highlights a selected sample site and an area which displays information to a user.
11. The deposition aid of claim 1 , further comprising at least one of an interface for the manual confirmation of the deposition and a device for the automatic detection of a manual deposition process.
12. The deposition aid of claim 11 , wherein the device for automated detection comprises a scattered light sensor that detects changes in scattered light behavior on the sample support, which changes are indicative of a manual deposition process.
13. The deposition aid of claim 11 , wherein the interface for confirming the deposition comprises a scattered light sensor which detects manually produced changes in scattered light in a predetermined area of the sample support.
14. The deposition aid of claim 1 , wherein the non-orthogonal angle relative to the plane of the sample support is substantially greater than 15°.
15. A deposition aid for manual preparation of samples on a sample support for subsequent ionization via matrix-assisted laser desorption, the aid comprising:
a base plate containing a holder for a sample support which has several sample sites;
a guidance system which selects one of the several sample sites, based on configuration data of the sample sites on the sample support;
a vertical support located at one side of the base plate;
a video projector mounted on the vertical support that communicates with and is controlled by the guidance system and projects onto at least a portion of the sample sites, at a non-orthogonal angle relative to a plane of the sample support, at least one two-dimensional optical image that is constructed so that the selected sample site is highlighted with respect to neighboring, not-selected sample sites in a manner which can be perceived by the human eye; and
optics, including at least one of a lens and a mirror, that condition the image to be displayed substantially without distortion.