stepwedge

stepwedge

 [step´wej]
a device used for comparing exposure intensities in photography or radiography; a series of tones from white to black (photography) or plates of increasing thickness (radiography) are placed between the energy sources and the film and differences in exposure are noted.

stepwedge

[step′wej]
an aluminum device that, when exposed to x-rays, displays a range of exposure intensities on a radiograph. These exposure "steps" are analyzed to determine the speed characteristics of the radiographic film. Also called penetrometer.

stepwedge,

n an aluminum device that, when exposed to roentgen rays, displays a range of exposure intensities on a radiograph. These “steps” are analyzed to determine the speed characteristics of the radiographic film. See also penetrometer.

stepwedge

a block of aluminum shaped like a series of steps. Used to test the characteristics of the x-ray beam, film, filters and to standardize exposure factors.
References in periodicals archive ?
The aluminum stepwedge was fixed to the radiographic sensor on the longer side (BARBOSA et al.
To measure relative bone density, an aluminum stepwedge is normally used in research as a unit of reference for density measurement, which enables a correlation between the values of bone and metal.
1] by selecting areas of interest in bony regions and the steps of the aluminum stepwedge that showed similarity between the gray tones.
5 cm x 1 mm), which contained a graduated aluminum stepwedge varying from 1 to 10 mm in thickness and uniform steps of 1 mm each.
Both materials overcame 3 steps from the aluminum stepwedge, which is the minimum recommended by ANSI/ADA specification 57 [24], whereas the pozzolan Portland cements did not meet this requirement (109.
Intensity calibration was carried out using an intensity stepwedge prior to gel image capture.
Beyer-Olsen, Orstavik [1] (1981) included in their studies a reproducible comparison standard using a 2-mm-increment aluminum stepwedge to determine the radiopacity of several root canal sealers.
Rochester, NY, USA) next to a graduated aluminum stepwedge with thickness ranging from 2 to 16 mm (in 2 mm-increments) and exposed using a GE-1000 X-ray unit (General Electric, Milwaukee, WI, USA) operating at 50 kVp, 10 mA, 18 pulses/second, and focus-film distance of 33.
Bone mineral density measurements were performed on the panoramic radiographs with the help of a five-step copper stepwedge phantom, attached to each film cassette, which was calibrated before hand by DEXA.
Exposure times were determined using a stepwedge to calibrate densities of the three film-speed/collimator combinations to a particular step on the wedge.
This method is specifically indicated for research related to stepwedge penetrometer and photodensitometer.
Este metodo se indica especificamente para la investigacion con el penetrometro stepwedge y el fotodensitometro.