Imaging spatial resolution

Figure 2 Effect of enzyme immobilization on luminescent image spatial resolution evaluated using coupled enzymatic reactions on nylon net as a model system, (a) Immobilized 3a-hydroxysteroid dehydrogenase (b) immobilized 3a-hydroxysteroid dehydrogenase and FMN-NADH oxidoreductase (c) immobilized 3a-hydroxysteroid dehydrogenase, FMN-NADH oxidoreductase, and bacterial luciferase. (From Ref. 47. Copyright John Wiley Sons Ltd. Reproduced with permission.)...

Chan, K. L. A. and Kazarian, S. G. (2003) New opportunities in micro- and macro-attenuated total reflection infrared spectroscopic imaging spatial resolution and sampling versatility. Appl. Spectrosc. 57, 381. 

In film-based imaging, spatial resolution is often assessed by determining the limiting resolution in terms of line-pairs/mm from a bar pattern. This is a subjective test, however, and is not very useful in the analysis of complex imaging systems. 

One very important property to remember about collimators is that the spatial resolution gets worse as the source-to-collimator distance increases. This is illustrated in the set of phantom images that were acquired from 5 to 30 cm from the collimator surface. To obtain the best-quality images, spatial resolution comes at the price of count sensitivity therefore it is crucial to keep the collimator as close to the patient as possible. 

Spatial resolution of an analytical technique defines the ability to extract and separate analytical information from regions of a sample with a typical diameter in the range of microns. The novel aspect of spatial resolution is to image the distribution of elements or compounds across the sample surface. The in situ analysis of microscopic areas of the work of art may be accomplished by spatial resolution, thereby the extraction of a wide range of valuable analytical information can also be visualized with an image. Spatial resolution also allows for the analysis of tiny fragments of samples scraped from the object of interest with minimal damage to the artifact itself. 

Until recently, limitations in spatial resolution made PET studies in small animals impossible. Eor instance, most PET scanners in clinical use have an image spatial resolution of 10-15 mm (although more recent instruments can achieve resolution approaching 1-2 mm) the mouse lung, in contrast, is 10mm wide. Other issues such as scanner sensitivity (i.e., the fraction of radioactive events actually detected by the device) and the amount of radioactivity... 

Spectroscopic mode also referred to as Bunched mode. This is used when optimal secondary ion mass resolution is needed. Note This comes at the cost of image spatial resolution. 

Instantaneous field of view (IFOVf The angular projection of the detector element at the target plane Imaging spatial resolution. 

The TFOV of an IR Camera is, essentially, the projection of the focal plane detector array at the target surface, and the IFOV is the projection of a single detector element. TFOV and IFOV are illustrated in Fig. 3.6 that also describes how the total target size and imaging spatial resolution at any given working distance may be calculated from manufacturer s specifieations. 

For thermal imagers, the IFOV expresses spatial resolution for imaging purposes but not for measurement purposes. Measurement instantaneous field of view (IFOVmeas or MFOV) expresses spatial resolution for measurement purposes. The modulation transfer function (MTF) is a measure of imaging spatial resolution. Modulation is a measure of radiance contrast and is expressed ... 

Performance parameters continue to improve. Where the measurements are made under controlled or laboratory conditions, extremely accurate and dependable measurements result. One model, the QFI InfraScope III, provides true temperature measurement on microelectronics targets with full field emissivity compensation and spot sizes down to 2.5 pm. On some portable models of FPA imagers, it is currently possible to achieve thermal resolution better than 15 mK (milliKelvins) (0.015°C) with imaging spatial resolution better than 3 pm on live targets. 

The producer of these maps is the CERSAT that is part of IFREMER. They are compiled on the basis of satelhte SSMI and QUIKSSCAT images. Spatial resolution of these charts is 12.500 meters (Erzaty and others, 2007). An example name of file is YYYYMMDD.nc. Examined files were downloaded firom the website ftp //ftp.ifremer.fir/ifremer/cersat-/products/gridded/psi-... 

Figure 12.11. Imaging-mode MALDI-IM-MS of a thin tissue section (16 rm) of a rat brain, (a) Structures of glucosylceramide and galactosylceramide, the two major classes of cerebroside molecules. Both cerebrosides are glycosphingolipids, which are impmlant components in nerve cell membranes, (b) Integrated mass spectrum obtained at the specific IM-ATD for these cerebrosides directly from rat brain tissue, (c) False color image of signal intensity for where these cerebrosides occur spatially in the context of the thin tissue section. Imaging MALDI-IM-MS was perfimned at 349 nm using a 2-nm Au nanoparticle matrix, with an imaging spatial resolution of 200 pm.

---