Why can't I change the chart with the remote?
Please click here for the Acuity ProTM Remote Troubleshooting Guide. If you are still unable to resolve the problem, contact us at 580.243.1301 or firstname.lastname@example.org.
Why does my remote not work after my computer sits idle for a while or goes to screen saver or hibernates?
When Windows hibernates or goes to screen saver mode, sometimes it loses connection with USB devices. To correct the problem, right click on an open area of your desktop; click on properties; then settings; then screensaver. From there turn off screensaver if on; then click on power option; set everything to “never” as in never turn off monitor; never hibernate, etc. You can also access these settings in your computers control panel, then under settings, or power options.
How do HOTV optotypes compare with Lea Symbols for preschool vision screening?
The 2010 study “Effect of age using Lea Symbols or HOTV for preschool vision screening” concluded “most children (>95%) completed both tests, with no statistically significant differences.” Ref: Cyert, L. et al. Effect of age using Lea Symbols or HOTV for preschool vision screening. Optometry and Vision Science 2010 Feb; 87(2): 87-95.
What if I lose my hardware license key or license CD?
We are not responsible for lost, stolen or damaged license keys. Replacement keys may be purchased at the normal retail fee for extra licenses. If a key becomes non-functional, it may be sent back to us for evaluation and if found defective, will be replaced at no charge. Please note that insurance should cover the cost of replacement license keys when damaged by fire, flood, etc.
Is Acuity Pro Windows 10 compliant?
Yes, Acuity ProTM has been tested with Win 10, 8.1, 8 and 7. However, we urge you to use the most current version of Windows. If you plan on using dual monitors, ensure you have a dual video card with a driver for the version of Windows you are using.
What Are The Hardware Requirements For Acuity Pro?
Acuity ProTM requires a minimum of 64 megabytes of RAM, a hard drive with 400 MB of free space, two free USB ports, a sound card and a video card capable of 1024 x 768 resolution. We recommend a 20″ or larger flatscreen monitor. If you require a video cable longer than 6 to 10 feet, it is imperative you purchase the highest quality ‘no signal loss’ cable you can find.
I already have a computer in my exam room, do I need a second one for Acuity Pro?
No. If you already have a computer in your exam room, you can add Acuity Pro to it. Acuity ProTM does not require a dedicated computer. You will need a dual head video card. This allows you to open a different program on each monitor. For example, your desk/primary monitor will display Electronic Health Record (EHR) software while the second monitor displays Acuity Pro. For a detailed explanation of how to do this, click on ‘Start’ then ‘Help’ and do a ‘search’ for ‘multiple monitor’. Windows help will explain what you need and how to set it up. *NOTE – With the release of v7.0.5, Acuity Pro will now allow mixed monitor sizes, aspect ratios and resolutions. If you add a new dual head video card, disable the original single output video card.
Should I use a mirror system or have a direct view for a short room?
Many doctors ask how short rooms affect refractions when trying to decide whether to setup exam rooms as direct or mirrored. Only light coming from an infinitely distant source is parallel. Light coming from a source closer than infinity is divergent. This is independent of accommodation or calibrated optotype size. When recording final refractive error, the patient distance to the chart must be taken into consideration – this is true for any target (paper chart, bulb projector or digital acuity system). If spectacle lenses have a 1/8 diopter tolerance and we cannot prescribe but in 1/4 diopter steps, then we only need to be concerned about room distances that have more than 1/8 diopter of divergent light from the target source, the eye chart. Twenty foot rooms have been considered ‘optical infinity’. If you do the math, a 20 foot room has a divergence of .164 diopters (more than 1/8 (0.125) diopter), in other words, the light is diverging from a 20 foot source at .164 diopters. The doctor should add .164 diopters of minus (less plus) to all phoropter readings to be exact in prescription. However, since .164 diopters is less than 1/4 (.25) diopter, and that is the least change that can be made in spectacle prescriptions, most doctors prescribe directly from the phoropter. In actuality, since .164 is greater than 1/8 diopter, the doctor would be less in error by making the 1/4 diopter adjustment. The doctor would need to have a room longer than 26 feet to drop below the 1/8 diopter divergence! The following table illustrates room distance effect on final prescription.
Optical distance in feet Divergence of light in diopters
The other issue occurs when assessing unaided acuities. If a patient with 0.5 diopters of myopia is sitting in a 6.5 foot room (patient to target), the patient may easily read 20/15 or 20/10. Light from the target is diverging at a rate inversely proportional to the distance of the observer. Light diverges by 0.5 diopter and a myopic eye converges it by 0.5 diopter causing the chart to be in focus. There is nothing wrong with using short rooms with direct viewing of targets. However, remember to adjust refractions by the appropriate amount and be aware of inaccurate unaided acuities. Refer to diagram below.
Why is Acuity Pro not centered on the secondary monitor?
If you are using an older version of Acuity Pro (before v7.0.6) you may need the update, which can be found on our Downloads page here. If you have the latest version and have added a dual head video card to your computer, you may need to disable the onboard video card through the BIOS or by going to Device Manager and disabling it there.
Does Acuity Pro meet ANSI standards for luminance, contrast and color temperature?
- The standard for optotypes as specified in ANSI Z80.21-1992 (R2004) states that the standard background luminance shall be 160 Cd/m2 with a range between 80 – 320 Cd/m2. Some competitive products such as those ‘chart-in-a-box’ type devices have a stated luminance of 80 Cd/m2 with a 10% tolerance. That would actually put them below the ANSI standard! All computer monitors easily provide luminance ranges of 80 – 320 Cd/m2. This allows Acuity Pro to operate on ‘off-the-shelf’ computer hardware and be ANSI compliant.
- Contrast ratios for flat screens far exceed the requirements for ANSI (document ISO 8596), which is stated as “…dark optotypes on a lighter background and the luminance of the optotype shall be equal to or less than 15% the luminance of the background”. Contrast ratios for computer monitors are typically 300:1 at the low end and many are now 600:1 and greater. This far exceeds the minimum requirements of ANSI for contrast.
- Color temperature (what color is white) for optotype background is specified in the International Organization for Standardization (ISO) document ISO 8596:1994(E). It states that the white light of the background of optotypes will be within the range of 2500K and 7000K. Virtually all computer monitors produce white light in this range. To be more specific, most are pre-set to the sRGB standard of 6500K, which is a standard that Microsoft and Hewlett Packard established as the optimum ‘white’ for computer monitors. 6500K is also referred to as the ‘average summer daylight’ white.
- The bottom line is that modern computer monitors produce luminance, contrast and color temperatures that easily meet or exceed all ANSI standards for visual acuity testing.
Why do the red/blue glasses not completely block out the opposite colors on the 4 dot test and the fixation disparity chart?
The red/blue screens have not been calibrated. In the 4-Dot screen and the Fixation Disparity Screens press the ‘H’ key then:
Step 1: While wearing Red/Blue glasses, cover your left eye (blue lens) and adjust the BACKGROUND slider so that the blue dots/bars disappear into the background.
Step 2: Now cover your right eye (red lens) and adjust the red slider until the red dot/bars disappear into the background.
NOTE: Try setting your Brightness and Contrast about 30% each and setting your RED, BLUE and GREEN screen colors at about 75%. This general rule seems to be a good place to start.
* Monitor brightness and screen colors are set by physical controls on your monitor, not through software, read your monitor manual for details.
Why do I have to re-connect and re-calibrate Acuity Pro every time I start it? It doesn't remember my preferences.
This problem has been resolved with the latest update of Acuity Pro. Background: This problem is a permissions issue created by Windows security features. Acuity Pro MUST be installed while logged on as an Administrator. Preferences like calibration, macros, remote control COM port assignments and other things are saved to a special file that requires read and write privileges. Non-Administrators do not have the authority to “change” or write to files and as such, cannot “save” their preferences. If everyone has administrative privileges, there is no problem but if you don’t want all users to have admin privileges, an update too the latest version is needed.
Why do the round letters appear to have 'jaggies' when viewed at close distance to the screen?
There are two ways to display graphic images on computer screens, bitmapped images and vector based images. Vector based images are mathematical descriptions of the shapes to be displayed while bitmapped images are a set of stored points. The bitmapped images are inherently ‘jaggy’ on any curved or diagonal edge so most software ‘blurs’ the edges of the image with a technique called anti-aliasing. This technique ‘fills in’ the missing spots on the edge with a smattering of half tones to attempt to smooth the edge. Acuity Pro has chosen to use vector based images. We don’t want to blur the edges of the optotypes just so the image will look ‘pretty’ when viewed up close but rather what we do want, is the sharpest edge and highest possible contrast between the optotype and the background. After all, we are checking acuity, let the visual system do the ‘anti-aliasing’ not the computer.
Why don't the Os and Cs appear round? What is the 'Screen Symmetry' adjustment for?
You need to adjust the horizontal and vertical aspects of your monitor. Start Acuity Pro then press the ‘H’ key to unhide the control panel. Click on the button labeled ‘Calibrate’. Now click on ‘Screen Symmetry’. Get a millimeter rule and place it on the screen. Measure the height and width of the box. They should be equal. If they are not, the optotypes will not be the correct shape and proportion. There are two ways to correct this problem. The best way is to change the settings of your monitor so that the horizontal and vertical ratio is correct. Try changing the screen resolution first. This may correct the problem. If not, you will need the manual that came with your monitor to determine how to adjust the height and width of your monitor. Make the adjustments so the square is just as high as it is wide. One other thing that can affect the ratio of height to width is the ‘stretch’ feature of some monitors. If you have ‘stretch’ turned on, the screen will distort itself to fill the entire screen with the output. This can make the images out of proportion. Again, check your manual to see how to change this from stretch to normal. If your monitor does not have controls to make these adjustments, you may use the ability of Acuity Pro to make this adjustment. Measure the box and click on the scroll bar buttons to change the width of the box.
Why do the optotypes have a 'ghost' image around them?
You either have a defective monitor cable or you are using a monitor cable that is too long. Maximum distance for a monitor cable is between 6 and 10 feet. Anything longer than that will cause ghosting unless you use a very high quality video cable (see Question above regarding Hardware Requirements). We suggest keeping the monitor cable as short as possible. Put the computer near the screen and use a wireless keyboard.