摘要
目的通过对干式与湿式激光打印机照片质量的测试、比较,正确评价两者的成像质量及其各自的优缺点。方法①在相同显示参数下,将成像主机内置SMPTE测试卡分别输入到干式与湿式激光打印机进行打印。对打印后测试卡图像所能显示的7种功能指标进行测试、分析和比较。②利用显微密度仪对两种SMPTE卡打印片的均方根颗粒度值(RMS)进行测试。③选择颅脑、肝脏、腰椎和胸部四组CT图像,在相同显示参数下分别输入干式和湿式激光打印机进行打印,对打印的图像进行主观评价。结果①从两种激光打印机打出的SMPTE标准测试卡图像中测得的灰阶密度的线及其余6项功能显示指标,都基本相同;②均方根颗粒度测出值,干式最大为3.285×10-2,湿式最大为2.506×10-2;③四组CT照片盲审评价结果表明在对两种打印机图像的评判上存在主观差异,主要的分歧点在于两种图像的黑化度及信噪比上。结论干式与湿式激光打印机打印出的照片质量,物理指标评价,两者基本一致。临床应用主观评价,各有自己的特点,干式的对比度和噪声略高于湿式,适于颅脑CT的观察,而湿式更适于腹部CT的观察。
Objective To test and compare the image quality printed by“dry ”a nd “wet”laser printer in order to appreciate the image quality of two differen t printing ways and corresponding advantages and disadvantages.Methods ①With sa me display parameters,to print the modality built-in SMPTE card by “dry”and “wet”laser printer,to test,analyse and compare the seven function indexes of two different printed SMPTE card images.②To measure the RMS(root mean square)v alues of printed SMPTE card images with the help of microdensimeter.③To select four groups CT images of brain,liver,lumber and lung which were displayed with t he same parameters,to print these images by “dry”and “wet”laser printers,the n to make subjective evaluation of these printed images.Results ①The greyscale -density curves and other six function indexes of the SMPTE card images printed by two different printing ways were roughly same. ②RMS values:the maximal RMS value for “dry”laser printer was 3.285×10-2,while “wet”laser printer was 2.506×10-2.③There was subjective difference in the evaluation of the four gr oups CT images,and the main focus was on the density and signal-noise ratio of these printed images.Conclusion The image quality and physical indexes evaluatio n printed by the “dry”and “wet”laser printer are fundamentally same.The subj ective evaluation of clinical application is that everyone has its own character istics,such as the contrast and noise of the “dry”laser printer is a bit highe r than the “wet”one,so it is more suitable for observation of brain,on the oth er hand,the “wet”is more suitable for the observation of abdominal CT images.
出处
《中国航天医药杂志》
2003年第2期31-34,共4页
Medical Journal of CASE
