Monitors for CAD20 Mar, 2013 By: Curt Moreno
Cadalyst Labs Report: Before you make your next monitor purchase, learn how to choose options that will meet your needs and take a look at six current models that we put through their paces in Cadalyst Labs.
Editor's note: Cadalyst has published an updated version of the following resource for 2017, outlining advice for selecting the best monitor to support the CAD workflow. See Choose the Best Type of Monitor for CAD, from the editors of Cadalyst.
We don't think twice about spending a great deal of time researching and selecting the television that becomes the centerpiece of our living room, but when it comes to choosing the monitor that will be the centerpiece of our CAD workstation, the task often gets short shrift. Perhaps this is because picking the perfect monitor can seem daunting, especially when it comes to discussing aspect ratios and backlighting technologies.
But let's be honest: The monitor you select for CAD work — a component you likely rely on during the majority of your workday — deserves just as much consideration as any other component of your CAD setup. Wisely investing in a monitor can return dividends of a long service life, considerable energy savings, and a better user experience.
Determining the right option for your needs takes a bit of time and a good deal of understanding, but it needn't be difficult. In this Cadalyst Labs Report, I aim to deliver the information you need to make your next monitor upgrade a smart one, explaining the basics of today's technology and introducing you to six of the latest models on the professional market. I hope you come away feeling confident and ready to set out on your own monitor search.
Understanding the Features
Let's start with an overview of basic monitor features and what you need to look for in each category.
Size. Monitors are measured according to the portion of the display screen that is available for viewing. This measurement is traditionally taken diagonally, measured from one visible corner to the opposite visible corner.
These days, dual 19" monitors are considered the minimum for a CAD workstation, but even that setup can be limiting. Modern CAD applications have so many toolbars, palettes, and pop-ups that screen real estate is at a premium. That's why I recommend nothing less than dual 22" monitors for CAD professionals.
All monitors of the same size don't necessarily have the same available viewing area! This is due to aspect ratio.
Aspect ratio. This confusing term has a simple meaning: It is the relationship of the horizontal dimension to the vertical dimension, noted as a ratio of h:v. Today monitors are almost universally available in 16:9 or 16:10 aspect ratio. Both are described as widescreen in marketing materials, but the actual ratio should be clearly listed in the technical specifications. If you're not evaluating a monitor in person, be sure you're clear about its aspect ratio. Monitors that are the same size but different aspect ratios can be very different in appearance.
Resolution. Normally reported as width x height, a monitor's resolution represents the number of lines of pixels in each direction. So a monitor with a resolution of 1,920 x 1,080 has 1,920 lines of pixels from left to right and 1,080 lines of pixels from top to bottom. The general rule of thumb is that the greater the resolution (that is, the more lines of pixels), the better the image quality; however, to get an accurate indication of image quality, you must consider resolution in conjunction with monitor size. That determines pixel density.
Pixel density. Monitors are designed for specific viewing distances. The closer a user is to the display, the more noticeable — and annoying — each individual pixel becomes. Pixel density indicates how many physical pixels are in a given area, normally one square inch, and expressed as a pixels per inch (PPI) value. The higher the PPI, the more compact the pixels and the less noticeable they are. Modern desktop monitors are commonly in the range of 90 to 100 PPI. This is an acceptable PPI range and generally considered the "sweet spot" for both manufacturers and consumers.
Another common term used to describe the number of pixels displayed is dot pitch, a linear measurement of the distance between pixels on a display that is usually reported in millimeters. The smaller this distance, the greater the pixel density and the less noticeable each pixel will be at close distance. An acceptable dot pitch for CAD professionals is in the range of 0.22–0.31 mm; anything more would probably result in poor performance for fine CAD linework.
Response time. Response time is how long it takes a pixel to transition from one color to another color as the monitor image changes, normally measured in milliseconds. Monitors with a slow response time will produce moving images that appear blurry or smeared. It wasn't too long ago that a response time of 16 ms was considered suitable, but today's monitors offer response times as short as 2 ms. While preferences and prices vary, a good rule of thumb is to stay in the range of 5–10 ms for the best viewing experience and value.
Panel type and viewing angle. Several different types of display panels are available to choose from when specifying a new workstation monitor. Twisted nematic (TN) is a common type of liquid-crystal display (LCD). TN panels are quite affordable and once dominated the market, but suffered from somewhat limited color performance and viewing angles. Newer, in-plane switching (IPS) displays are quickly becoming the norm for high-end graphic performance because they deliver greater color ranges and wider viewing angles.
Viewing angle determines the visibility of the display when viewed from the sides. The closer the viewing angle comes to 180 degrees, the more visible it is from the side. Naturally, CAD professionals spend most their time squarely facing the monitor. However, if your workspace hosts group collaborations or if the monitor is intended for training purposes, then viewing angle can be an important consideration.