| Question | Answer |
| the degree of geometric sharpness or accuracy of the structural lines actually recorded in the image | recorded detail |
| recorded detail is also referred to as what | definition, sharpness, spatial resolution, or detail |
| This term is applied to quantified discussions of recorded detail | spatial resolution |
| The primary unit of resolution is what | line pairs per millimeter or cycles per millimeter |
| Most human visual acuity is limited to what | 5 lp/mm |
| digital imaging recorded detail is determined primarily by what | matrix size, pixel size, and gray scale bit depth |
| How is spatial resolution measured | point spread function (PSF), line spread function (LSF), modulation transfer function (MTF), and system noise |
| The art of radiography involves controlling the degree of ____ so that it does not interfere with image diagnosis | unsharpness |
| This describes that ability of an imaging system to accurately display objects in two dimensions (three dimensions in digital imaging) | spatial resolution |
| Point spread function (PSF), Line spread function (LSF) and Edge spread function (ESF) all express boundaries of an image which in conventional radiography is called | penumbra or blur |
| High spatial resolution represents a high frequency signal that is capable of imaging what size objects | small |
| The higher the spatial frequency the | closer together the line pairs |
| this measures the accuracy of an image compared tot eh original object on a scale of 0 to 1 | modulation transfer function (MTF) |
| An MTF of 0 represents what | no signal/ no image |
| An MTF of 1 represents what | a signal of such extremely high fidelity that is records the image perfectly |
| This is background information that the image receptor receives | imaging noise |
| this refers to a lack of sufficient incoming data for processing. | quantum noise aka quantum mottle |
| This is the processing algorithm that averages the incoming analog data by using the distance between the imaging detector elements | nyquist criterion |
| this occurs when the nyquist criterion is violated (when spatial frequency exceeds nyquist frequency) | allasing |
| Resolution problems should be approached in this order: | 1.eliminate motion
2.reduce OID
3.reduce focal spot size
4.reduce intensifying screen size
5.increase SID |
| This is the imperfect, unsharp shadow surrounding the umbra | penumbra |
| Radiographic film usually has resolving capabilities in the range of | 100 lp/mm |
| The resolving power of an intensifying screen depends in three factors which are | phosphor size, phosphor layer thickness, phosphor concentration |
| phosphor size increases, resolution decreases, density increases, and patient dose | decreases |
| phosphor size decrease, resolution increases, patient dose increases, and density | decreases |
| layer thickness increases, resolution decreases, patient dose decreases, and density | increases |
| layer thickness decreases, patient dose increases, density decreases, and resolution | increases |
| phosphor concentration increases, resolution increases, density increases, dose | decreases |
| phosphor concentration decreases, resolution decreases, dose increases, density | decreases |
| The major factors that limit photostimulable phosphor systems are the | intensifying screen and scanning system |
| The major factor that limits indirect and direct digital systems is the | size of the detector element |
| What effect does increasing SID have on recorded detail? | increases |
| What effect does decreasing SID have on recorded detail | decreases |
| What effect does increasing OID have on recorded detail | decreases |
| What effect does decreasing OID have on recorded detail | increases |
| What effect does increasing patient thickness have on recorded detail | decreases |
| What effect does decreasing patient thickness have on recorded detail | increases |
| What effect does increasing focal spot size have on recorded detail | decreases |
| What effect does decreasing focal spot size have on recorded detail | increases |
| What effect does increasing film/screen speed have on recorded detail | decreases |
| What effect does decreasing film/screen speed have on recorded detail | increases |
| What effect does good film/screen contact have on recorded detail | increases |
| What effect does increasing motion have on recorded detail | decreases |
