We have installed 21" TFT 2M pixel monitors to each clinical area so that they have at least 1 good quality monitor to view images. Along with this we have purchased the QA package from the company and this allows for the monitors to be checked using test patterns at specified intervals. To make life easier we have also bought the add-on network package which collects the information supplied by the individual machines and allows a system administrator to check all of the monitors at the same time so any which have failed the test or are faulty will be easy to spot.
posted on Wednesday, November 16, 2005 - 01:29 pm
I know that NEC displays achieved pre-qualification to DIN 6868-57, this maybe the DIN ref that you are looking for, and yes! these are the ones we deal with. To cover myself though, i am sure others do too.
The guidance (based on the AAPM) does not cover the related issue of recommended display resolution of diagnostic/review workstations. This is because for monitor QA resolution testing the image is displayed at a 1:1 i.e. 1 display pixel: 1 image pixel (100% image size resolution). It therefore does not take into account the effect of interpolation that occurs when an image is minified to be displayed on a lower resolution screen. I'm working on guidelines on this for the RCR and I'll post more on this for comment shortly.
Mark, the attachments are not sent with the email notifications - to do with mail box sizes and security. The attachment is on the website however, just follow the link to the discussion at the bottom of the email.
Is there any information in terms of high resolution LCD monitors (B/W & Colour -3.5megapixel & 5Megapixels) as to when a monitor is deemed no longer usable when it has pixel failures. Is it a set number of pixels or percentage? Is it related to whether the pixels fail to red or some other colour? Where do we stand with B/W monochrome monitors on this? Has this been decided by some national or international body? Suggestions or pointers please. thanks, Will
The vendor should have specifications for when a monitor is deemed no longer usable as well as it should be stipulated in the agreement/warrantee. Additionally there should be a specified maintenance schedule to follow where a photometer (puck) is used to calibrate the monitor. Lastly with regards to pixel failure on the monitor, it depends on the regulations because if there is some pixel failure on the sides of the monitor, this might acceptable to the users. If pixel failure is occurring in the main/middle portion of the viewing area, this type of issue would need to be brought to the attention of the vendor.
posted on Thursday, September 21, 2006 - 09:39 am
There is also the issue of grouped failed pixels that are joined. There are specifications on what number of pixels are deemed a cluster etc. I contacted the manufacturer we received our medical grade monitors from to obtain there criteria on 'failed monitors'. This was a very black and white document, pardon the pun, with specific criteria on the number and location of failed pixels both individually and clustered. I believe a failed pixel in a LCD monitor will revert to its no power inherent state, black I believe. I am open to correction on this though!