FAQ - Polygon400 Related

1. How do I know if Mightex's Polygon400 can fit onto my microscope?
[A] Mightex's Polygon400 should fit on most upright and inverted microscopes made by Leica, Nikon, Olympus and Zeiss. On this page, you may find all the microscope adapters that Mightex has to offer as of today:http://www.mightexsystems.com/family_info.php?cPath=245_274_276&categories_id=276. If you have a microscope that is not currently supported, please contact us by email at sales@mightex.com or by phone at (USA) +1-925-218-1885, and let us know your microscope's details including make&model as well as the critical dimensions. Our technical team will be happy to look into the feasibility of fitting the Polygon400 onto your microscope.

2. In Color Image mode of Polygon400, why do I observe a 60Hz square-wave intensity profile while the Polygon400 is outputting a constant image pattern?
[A] Color Image mode is the field-sequential color display mode used in common video displays. In field-sequential color display each prime-color field is displayed in rapid succession. For this reason each of the three wavelengths is turned on ~1/3 of the time, resulting in the observed square-wave intensity profile.

In order to obtain constant optical intensity, you can use the Pattern Sequence Mode with duty-cycle set to 100%. Alternatively, if you have an “E” model of Polygon400 you can use black-and-white (no color) patterns while applying a constant illumination.

3. While my Polygon400 is outputting a constant image pattern, I measured a much higher intensity in Pattern Sequence mode than in Color Image mode. Why is it?
[A] As stated in FAQ#2 above, Color Image mode is the field-sequential color display mode used in common video displays. In field-sequential color display each prime-color field is displayed in rapid succession. For this reason each of the three wavelengths is turned on ~1/3 of the time resulting in lower average intensity than the intensity in Pattern Sequence mode with 100% duty-cycle.

4. I would like to load a large number of patterns to my Polygon400, but it is very time consuming to load them one by one. Is there a way to batch load the patterns? Also what's the maximum number of patterns that can be loaded to Polygon400?
[A] Yes, you may "Batch Load" multiple predefined patterns (in bitmap format) by following the instruction below:

1) In pattern sequence mode: Determine the total number of patterns that will be uploaded to the Polygon400, and input that number in the “Pattern Number” box.

2) Confirm all other Pattern Sequence settings, then click the [Set Pattern Sequence Settings] button.

3) In the main drawing window, set the “Pattern Index” to 1.

4) Click the [...] button to open a window to select your desired patterns (in bitmap format) for uploading. You can select multiple bitmaps in this dialog box.

5) The number of bitmaps selected MUST equal the number you specified in step 1, “Pattern Number” box.*

6) Once you have selected your desired bitmaps, click the [Upload All] button.

7) After the upload is complete, you may begin your pattern sequence.

*Note: (i) When using batch upload, one must select all patterns at once, starting from Pattern Index 1, otherwise the patterns will not upload. For example, if the user already has 100 patterns uploaded previously and wants to change patterns 51-100, he cannot set the Pattern Index to 51 and then select 50 patterns to replace patterns 51-100. However, he can still swap out bitmaps individually as normal; (ii) The order in which you select multiple files does not matter. The program will always upload them according to the order they appear in the file selection dialog. So even if you select multiple bitmaps in a random order, they will be ordered in the pattern index in relation to how they are ordered in the dialog.
The maximum number of patterns that can be loaded into a Polygon400 is >1,000.

5. On some microscope models, I have observed multiple images and/or scattered background illumination around shapes projected by Polygon400. Why?
[A] This is most likely caused by the reflection from the condenser that is located below the microscope objective, and NOT caused by the Polygon400 itself. The Polygon patterns bounce off the condenser, and create multiple images of the patterns projected by the Polygon400. There is nothing wrong with the Polygon400 (nor is there anything that can be done on the Polygon400), and the best fix is (for example) to insert a thin sheet of black paper between the objective and the condenser, which should block the reflection.

6. How can I produce patterns with gray levels? Why do I observe time-domain modulation when displaying patterns with gray levels?
[A] Polygon400 is based on Texas Instrument’s DLP, which contains an array of micro-mirrors and each mirror can only assume two distinct positions. One position of the mirror will reflect the incoming light into the optical path (i.e. ‘bright’), and the other position will reflect the light away from the optical path (i.e. ‘dark’). Therefore, a DLP-based device can only support 1-bit static patterns. The only way to achieve higher bitdepth gray level patterns is by controlling the On/Off time ratio in time domain through modulation. For example, in order to achieve a 2-bit gray level pattern with four (4) gray levels (i.e. 0, 1, 2, and 3), the DLP will operate in the following fashion:

In short, with gray level “0” the mirror is always in OFF position, with gray level “3” the mirror is always in ON position, while gray level “1” is achieved by leaving the mirror ON for 33% of the time and OFF for 67% of the time, and gray level “2” is achieved by leaving the mirror ON for 67% of the time and OFF for 33% of the time. For some applications, this kind of time-domain modulation is undesirable and, in such cases, ONLY 1-bit patterns should be used.

7. After launching PolyLite software, the drawing window does not show. Why?
[A] It is likely that, when you last quit the software, the Drawing Window was moved out of the effective viewing area of your computer screen (e.g. on a secondary monitor). The previous location of the drawing window was stored in a data file named 'AppPara.ini" and it will be applied when you re-launch the PolyLite software. This is why the Drawing Window cannot be seen as it is now located outside your computer screen's effective viewing area. In order to solve the problem, you can locate the file “AppPara.ini” on your hard disc, where you have copied&saved the PolyLite software. This file can be found in the folder “Application\MT_Polygon400_SDK”, and you may simply delete the “AppPara.ini” and then re-launch the PolyLite software. Deleting “AppPara.ini” will not do any harm, as this file only stores some initialization data including the screen coordinates of the Drawing Window. In abesence of the "AppPara.ini" file, PolyLite will then display the Drawing Window in the default location within the effective viewing area of your computer screen.

8. I have just updated my PolyLite software to the newest version, but now the software fails to detect the Polygon device. How can I solve the problem?
[A] It is most likely that the new/updated PolyLite software is not able to find the Polygon device-spcific configuration files. Please make sure to copy all the device-specific configuration files from your original CD (or wherever you have saved the 'old' PolyLite software on your PC's hard disc). These files can be found in this folder: \Application\MT_Polygon400_SDK\AppData\DSIEeeeeeeeeeeeexxxxxxxxxxxx\” where “DSIEeeeeeeeeeeeexxxxxxxxxxxx” is unique to your Polygon device, and you may simply copy the entire folder “DSIEeeeeeeeeeeeexxxxxxxxxxxx” to the new folder \Application\MT_Polygon400_SDK\AppData” where the PolyLite software is saved.

9. What are the advantages of using a three-position microscope adapter?
[A] A three-position microscope adapter will allow you to mount up to three (3) mirrors (partial or dichroic) and to select the one that will best fit the experiment that you are conducting, without the need to physically remove/replace the mirror. You may also choose to leave one of the three positions 'empty' (viz. without any mirror). If (for example) you want to use your existing dichroic mirror originally mounted on your microscope, you may simply use the slider on the 3-position microscope adapter to select an empty slot, and in this case the Polygon will be optically ‘removed’ from the micrscope’s otpical system, without the need to physically remove it. This way, all your existing systems should work just like before, as if the Polygon is non-existent. If however you want to use your existing system and the Polygon simultaneously, you may instead mount a dichoric into one of the three (3) slots in the 3-position microscope adapter. In fact, we have customers using Polygon for their fluorescence imaging applications as well, provided the optical wavelength in the Polygon works for their fluorophore. In short, the 3-position microscope adapter will give you a lot of flexibility in how to construct your system, and hence it will enable you to use your microscope system for many different applications.

10. I am using a DSI-E or a DSI-G model with PolyLite software, and the "Exposure Time" settings in the Pattern Sequence Mode does not work to turn on/off the patterns at specify?
[A] The “Exposure Time” setting in the PolyLite is only effective for DSI-I models with built-in LED and built-in LED controller. The way the DMD works is that the mirrors will always hold each pattern until the next pattern is displayed(i.e. mirrors hold each pattern with 100% duty cycle), and the "Exposure Time" settings tells the built-in LED to turn on and off accordingly using the built-in LED controller. This setting is ineffective for DSI-E model (built-in LEDs; external LED controller), nor for DSI-G (both light source and its controller are external), because the Polygon400 hardware/software have no control over the external light controller. In this case, the proper way to control the "Exposure Time" would be to turn on/off the light sources by settings in the external light controller, while letting the Polygon handle the “patterning” only.