Looking Glass Calibration

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By laminating special lens, called a Lenticular Lens on LCD panel, we can generate multi point view image and display on device. We see stereoscopic image front of screen, without 3D-glasses. Normally, lenticular lenses do not appear solidly as they fit perfectly with the constituent dots of the image, but it is extremely difficult and expensive to paste them accurately. So, Looking Glass seems to be able to use even if pasted inaccurate is adjusted by software. TO calibrate, the data of "lens tilt (tilted about 10 degrees )" "pitch of lens (seems to be about 50 LPI)" "gaps between center of lens and image center" have been stored device's firmware memory. In the standard application of Looking Glass, or the application using their SDK, these values are automatically recalled and displayed, so the user does not need to worry about it.
SPM dared not to use Looking Glass's SDK, so SPM make it possible to create display images and display on looking glass.

As an advantage, You can use only SPM to create and display images strait forward, and on an decent PC without a fast GPU board, if you can display an external monitor of 2560 x 1600 pixels, you can enjoy Looking Glass.
As a disadvantage, as described above, since calibration values stored in the main unit can not be read (information is not disclosed), we need to calibrate to get those values.
Please note that the description on this page does not guarantee accuracy on the basis of the personally examined contents.

Looking Glass specification ( Please inform me if it is different )
Screen size : 8.5 inches (Although it seems to be 8.9 inches in the initial lot, here we describe it with 8.5 inches version)
Screen resolution : 2560 x 1600 pixels
Pixel pitch: 355 DPI
lenticular pitch : 50 LPI (49.96 LPI?)
Lens affixing angle : Approximately 10 degree (It seems that it is quite scattered, information on 1 o'clock direction of the clock, initial lot is information on 11 o'clock direction.)
When the lens is pasted on vertically, RGB subpixel number per one lens : 21.31 pixels
RGB subpixel number when tilted 10 degree : 21.64 pixels

1. Start SPM and press Alt + C to open the Looking Glass calibration screen

2. perform the following setting
a) Screen size : Width:2560 Height: 1600
b) Looking Glass display position
Specify where in the multi display the Looking Glass will be placed in display setting.
Looking Glass recommends left (see the figure below).
Display 1 and 2 should be top aligned.
If it is correctly set, a diagonal line will appear in Looking Glass.

3. Lens Slant adjustment
Adjustment numbers can be entered directly by keyboard, but since the tilt is around 10 degree, Please set to -5.5 (1 o'clock direction) And, tune it by slider, slanted line to the center. Please adjust until it will not cut.
The value displayed on the right side of the slider is the adjustment value.
OK example (It is connected until you did from the top without diagonal lines)

NG example (the diagonal line is cut in the middle )

4. The lens pitch adjustment (rough adjustment)
When you press the "Auto Calc from Slant" button, the lens pitch is calculated automatically and set at the center of adjustment, so it should be very close, but you may perform fine adjustment.

Press the adjustment pattern "Wide Band". Adjust with the slider so that it becomes the same color on all sides.
I think that it is better to adjust by one eye. The viewing angle changes depending on the distance from Looking Glass, so the adjustment value may differ. Normally, please adjust at the position to watch.
OK example (It will be the same color all over)

NG example (RGB band can be seen)

5. Adjust lens Pitch (precise adjustment)

Press the adjustment pattern "Narrow Band". Adjust with the slider so that the width of each color is maximum. I think that it is better to adjust with one eye. The viewing angle changes depending on the distance from Looking Glass, so the adjustment value will change. Normally, please adjust at the position to watch. Even if it does not fit very strictly it seems to be okay.

OK example (The width of the same color becomes maximum.) Also, when you look at both eyes, you will see multiple colors. Please adjust with one eye.

NG example (RGB band can be seen)

6. Centering the lens
If the center of the lens is not aligned to the center of the image, Images will be flipped while you are viewing from right to left looking Glass.

Press the adjustment pattern "Centering" and adjust the slider so that the lines will overlap. Please align with the front center of the screen with one eye.

OK example (lines overlap)

NG example (lines can be seen apart)

7. Confirmation
press the lg_calib.jpg button, the image will be switched every time you press it, Please confirm that it is properly displayed in Stereo. Move your head to the left and right, and please confirm that it looks normal as much as possible. Please re-adjust if there is a problem.

8. Save settings
When you set it correctly, we recommend you to press the Save button, with a suitable file name. You can recall the setting with the Restore button.
If you want to use a different PC, if you copy and load the configuration file, you do not need to calibrate again

9. Complete Calibration
By pressing the OK button, the setting value is saved in the registry, so the value is retained even when you exit SPM. So unless you change the setting, use that value to display the looking glass. You only need to calibrate the first one time.