Title:
【発明の名称】X線自動露出制御装置
Document Type and Number:
Japanese Patent JP2954982
Kind Code:
B2
Abstract:
PURPOSE:To obtain proper concentration always by multi-dividing a lighted field of an x-ray detector for a luminance automatically controlled radioscopic image and calculating the ratio of an average value of each divided section and the whole lighted field and multiplying the ratio to an x-ray detector input at the time of taking a radiograph. CONSTITUTION:Stable concentration correction is carried out by correction reflecting the level of the surface area of each divided section. A multi-dividing circuit 13 has 9 kinds of integrators 141 to 149 corresponding to each divided section to divide a lighted field of a radioscopic image displayed on a monitor 6 into 9 divided sections 1 to 9. Integration of video signals whose luminance is adjusted automatically is carried out for each of the sections l-9 and the ratio of the maximum value in an average divided section of a region (surface area) equivalent to the lighted field of an x-ray detector to the integrated value is calculated. Next, an input signal of the x-ray detector at the time of taking a radiograph is multiplied by the obtained ratio, so that the signal of the x-ray detector lowered by a x-ray sensitive agent is able to be increased to a signal level at the time of no x-ray sensitive agent.
Inventors:
NISHIZUKA SEIICHI
KIMURA TATSU
KIMURA TATSU
Application Number:
JP15818490A
Publication Date:
September 27, 1999
Filing Date:
June 14, 1990
Export Citation:
Assignee:
TOSHIBA KK
International Classes:
A61B6/00; H05G1/44; H05G1/64; H05G1/30; (IPC1-7): H05G1/44; A61B6/00; H05G1/30; H05G1/64
Domestic Patent References:
| JP5875800A | ||||
| JP5773900U | ||||
| JP626320B2 |
Attorney, Agent or Firm:
Masayoshi Misawa