Construction of a Basic "Grade 1" 32" LCD Picture Monitor

newcoppiceman

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I'm a retired BBC-trained engineer who worked in Television Centre, London studios in the 1980s and latterly for Channel 4. In my work I encountered so-called "Grade 1" picture monitors used in places like studio galleries; their job was to add nothing to, nor take anything away from, the signals they were fed with. They used professional high resolution CRTs (with the original delta gun arrangement and EBU phosphors), had lots of adjustments (for things like convergence and beam landing), and gave stunning pictures, especially when fed RGB from the studio cameras. These monitors weren't TVs - they had no tuners nor any provision for audio.

I'm currently researching the prospects for emulating such monitors using HD and LCD technologies and would welcome input from the distinguished contributors to the various LCD technology/panel threads or from anyone interested in what I'm attempting.

The basic specification of the monitor is currently:

1 LCD Panel: 32" / 16x9 / 1920 x 1080 native resolution / 50Hz refresh rate (not 60Hz) / 10 bit
2 Input (at all times): 1920 x 1080 progressive / 50Hz frame rate / HDMI or DVI-D dual link

The monitor would be paired with a Lumagen Radiance XE video processor. This unit sets the industry benchmark for switching, calibration and video processing performance and employs 10-bit processing, per-pixel SD and HD deinterlacing with adaptive diagonal filtering, "no-ring" scaling technology and assorted artifact/noise reduction techniques.

At its most basic the monitor would consist of:

1 The LCD panel - this includes a driver PCB which accepts the LVDS video together with various control and power signals
2 An interface board which would accept the 1920 x 1080 progressive at 50Hz input and provide the LVDS video for the panel
3 A control board connecting to the interface board
4 Power supply - including panel backlight supply (xxFL or LED)

There are a number of development products and kits available which might perform the function of the interface/control boards. Assuming a basic design of interface board, here are a couple of questions:

Q1 Refresh Rate - With the system as so far described, is it relevant to consider (n x 50)Hz for the panel rather than a basic 50Hz? What are the pros and cons?
Q2 Contrast Ratio - Is the panel's inherent contrast ratio (say 1000:1) likely to disappoint in the absence of any of the "tricks" commonly used to achieve ratios of many times this?

Turning to specifics, one possible panel is the LG LC320EUD-SCA1. From its data sheet this LED-backlight panel is:

1 1920 x 1080 native resolution
2 1300:1 typical contrast ratio
3 450 cdm-2 white luminance
4 10-bit, 4-port LVDS interface

Applying the table at http://forum.ixbt.com/post.cgi?id=attach:62:14399:31:2 here are some more questions:

Q3 How does the EU designation fit in?

The D would appear to mean the panel is 120Hz - I've also seen an EUN, the 60Hz version, it seems:

Q4 Is the refresh rate variation purely a function of the panel's driver PCB rather than the panel itself?
Q5 Does the panel have to be 50Hz-specified for use at 50Hz refresh rate - or will a 60Hz panel work?

The S would appear to mean the panel is an IPS panel - not the best available type, so I should probably use an S- or AS-IPS panel

Next a question about the mechanical compatibility of the various panels available:

Q6 I'm considering buying a relatively new TV with a damaged panel, purely for the cabinet. Given the use of various manufacturers' panels by set makers are there standardised fixing points for a 32" panel so that the cabinet could be used for any (or almost any) 32" panel and not just the one originally fitted?

Finally...

Q7 Can anyone suggest a panel for my requirements - 32" / 16 x 9 / 1920 x 1080 / 50Hz / 10-bit / S- or AS-IPS?

That's it for now - please post with answers or thoughts on the seven Qs I've listed.
 

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