Lra 221 Quizzes Already Passed

Which of the following require more critical beam centering? a. parallel grids b. focused grids c. low-ratio grids d. low- frequency grids {Ans: focused grids}The exposure indicator number is a. an accurate measure of the patient dose b. an indication of radiation absorbed by the imaging plate c. both A and B d. none {Ans: an indication of radiation absorbed by the imaging plate}An image manipulation process that fills in the background so that it is darkened is known as a. window b. level c. shuttering d. Collimation {Ans: Shuttering}A highly efficient indirect conversion system that takes up less to fill space than CCD's is known as a a. analog to digital converter b. field-effect transistor c. CMOS d. thin field transistor {Ans: CMOS}Detector performance is measured with all of the following except: a. spatial resolution b. observation of flow contrast objects in a phantom c. DQE d. contrast {Ans: contrast}Window width controls the ratio of black and white, also known as a. window b. level c. contrast d. matrix {Ans: contrast}