EIZO EX3220-3D

This monitor uses a 3D LCD panel with an LED backlight, a brightness of 650 cd/m² and a contrast ratio of 1400:1. It displays in full HD resolution, and faithfully reproduces 3D surgical images for endoscopy and operation microscope feeds; creating a feeling of depth where stereoscopic imagery is required.

It has a viewing angle of 178 degrees so images can be viewed from various directions with minimal changes in contrast.

Reflections on the screen of LCD monitors are caused when external light hits the screen and reflects off of the glass and air layer at different refractive indices. Optical bonding technology minimizes the refractive index by bonding the LCD display with the external protective glass; removing the air pocket between, and reducing eye fatigue caused by screen reflections.

The protective glass used has a hardnes of more than 9H, making it difficult to scratch. Optical bonding improves the physical strength even more by injecting optoelastic resin into the air pocket between the LCD panel and external glass. Since there is no gap between the LCD panel and the external glass, damage to the LCD panel from dust and moisture can be prevented.

When using a monitor in an environment where the temperature can fluctuate severely, condensation may appear in the air pocket between the LCD panel and protective glass. Using optical bonding, there is no air pocket, meaning that condensation does not form and visibility is not compromised.

The CuratOR EX3220-3D uses a polarized system for displaying 3D images with excellent color characteristics and without flicker.

The supplied 3D polarizing glasses required to view images in 3D do not require batteries for operation and are lightweight. This makes them perfect for long surgeries where heavy, battery operated glasses may fail and become uncomfortable. Furthermore, the glasses have an anti-fog coating to prevent fog and maintain clear vision even when wearing a surgical mask.

The monitor support Side by Side, Line by Line, Top/Bottom, and SIMUL 3D signal formats.

The monitor supports various video input/output signals for connecting to various types of modality equipment. Furthermore GPI and RS-232C allows you to externally control 3D/2D display switching, input signals and screen rotation, so that you can change the display in conjunction with the settings of the surgical equipment being used.

The monitor is designed to dispel heat without the use of cooling fans. This creates a quiet, reliable monitor that doesn't interfere with the air flow in the operating room.

The monitor supports VESA mounting standards so that it can be installed in various locations such as from ceiling arms and wall hangings.

Humans are quite good at detecting depth on 2D images. We use a variety of ‘techniques’ to sense depth, be it from relative sizes of objects, motion, textures, lighting and/or focus. When watching a movie, even though it’s in 2D you still know exactly where everything is in relation to each other. But as you probably find when you try walking around with one eye closed, your depth perception, although enough to survive with, is not very accurate. You may find that you misjudge the height of a staircase and trip a little, or you try to catch a ball only to realize you missed it by a few centimeters. Humans can judge depth in 2D, but they cannot judge depth accurately. And that is why 3D technology is useful in surgeries where accuracy is vital. Stereoscopic surgery seems to be preferred by many doctors, as it allows a sense of depth that cannot be felt with 2D images. This is important in surgery, as injuries may occur to the patient if instruments are not placed in precisely the right position.

Polarized 3D technology displays images on a single screen, but uses a polarizer on both the monitor and the glasses, to create two different images for each eye. This is the technology adopted by our own CuratOR EX3220-3D and EX2620-3D surgical monitors. It has many advantages and is cost effective.

Polarized 3D technology works by passing light through a circular polarizer, making the light twist in either a clockwise or anticlockwise direction. On the glasses, the left lens will have a clockwise-polarizer, and the right lens will have an anti-clockwise polarizer. This means that the left lens will absorb clockwise-twisted light, and reflect anti-clockwise-twisted light. On the monitor, the clockwise and anti-clockwise circular polarizers are arranged in strips, so that one set of strips will be visible by the left eye, and the other set of strips will be visible to the right. To add video to this equation, you need two video sources taken from slightly different perspectives. The display device will arrange the image onto the screen so that the left camera’s video is displayed underneath the clockwise polarizers, whereas the right camera’s video is displayed underneath the anti-clockwise polarizer.

The active shutter 3D technique creates 3D images by quickly switching between the left and right camera feeds while blocking the left lens when the right image is shown, and blocking the right lens when the left image is shown. For each video frame, the monitor quickly changes from the left to the right camera feed. This means that for example, if a monitor typically displays one frame every second, a 3D monitor will have to display two frames every second – first the left frame and then the right frame. In order to separate these frames so that your left eye only sees the left image and vice versa, the glasses blacken the opposite lens in time with the switching on-screen. They do this by applying electricity to the liquid crystal lens of the glasses, which causes them to become opaque. As the left image displays on screen, the right lens blackens, and as the right image displays on screen, the left lens blackens.

The biggest reason that polarized 3D is preferred in surgeries is due to its safety and reliability. Because the polarization process does not require electricity, the glasses worn by the doctor do not require batteries like active shutter technology. This is vital in potentially long surgeries as batteries may fail halfway through, proving detrimental to the patient. Furthermore active shutter glasses often have ‘crosstalk’ where the synchronization of the display and the glasses becomes skewed, and the left image may leak into the right lens and vice versa. As polarized 3D glasses are static and do not require electricity, there is no possibility of the image becoming skewed – making polarized 3D more reliable. Furthermore, the lack of electrical components in polarized 3D displays makes production cheaper. Another advantage of polarized 3D is that there is no risk of flicker. Due to the rapid switching of images in active shutter technology, users often notice flicker which can cause headaches and discomfort. Polarized 3D technology does not carry this risk. Furthermore polarized 3D allows for brighter images than active shutter. However in order to create 3D images, some small disadvantages arise when compared to 2D. Polarized 3D technology displays images that are not whole, but rather divided into strips, which reduces the image quality compared to a 2D image. And active shutter can only show each frame for half the intended time that a 2D video would display. The other disadvantage is that many users find that they feel nauseous or gain a headache after prolonged use, due to the misalignment of the camera. Products like the CuratOR EX3220-3D have measures against this – and allow you to adjust the parallax of images to suit your eyes. Ultimately the advantages of 3D technology – especially polarized 3D technology – outweigh the disadvantages, allowing doctors to safely see surgical images with a sense of depth. The advantages and disadvantages are summarized below.