Using the Glassmark I Encoder

On this page, we'll go over the setup and operation of the Glassmark I Lens Encoder. The Glassmark I Encoder outputs 11 bit linear data, with an angular resoultion of .18 degrees. This makes is capable of detecting changes as small as a human hair!


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  1. Zero Button
    • Used to reset the encoder to Zero, or connect to WiFi
  2. Lens Gear
    • Replacable, interfaces with lens.
  3. Rod Clamp
    • Mounts Encoder to 15 or 19mm iris rods
  4. USB Port
    • Provides power to Encoder
  5. Cable Light
    • Illuminates USB port, indicates WiFi connection

Physical setup

Choose the gear that correctly interfaces with your lens. Gears can be replaced by using the included 1.5mm allen wrench. If your lens does not have a gear, you can utilize the Friction Wheel instead. Use caution when using the friction wheel, as it is more prone to slipping. Select the rod clamp that fits your setup, and slide it into the clamp groove. Tightening the knob will lock the clamp.


It doesn't matter which side of the lens you mount the encoders. When you Zero the encoder, it will report positive values no matter which direction it is spun.

Set the lens to the following settings:

  • Focus: Close focus
  • Iris: Widest aperture
  • Zoom: Widest focal length

Once set, press the Zero button to zero the encoder. You are now set.

Software Setup

If the encoder can not connect to WiFi, it will automatically create it's own configuration Access Point. This can also be manually triggered by pressing and holding the Zero Button within 3 seconds of powering up the encoder.

Connect to this access point with the following credentials:

  • SSID: Glassmark Encoder
  • Password: virtualreality

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Upon WiFi connection, a captive portal will open. Select Configure WiFi and enter the credentials of the WiFi network that the LONET server is running on. Also enter the IP Address of the LONET server, which is visible at the top of the LONET control software.

Select Save and the Encoder will automatically reset itself and attempt to connect to WiFi.


The Glassmark Encoder will only work with 2.4GHz WiFi networks.


The encoder is now configured, and will remember this information until it is manually reset.


  • Weight: 97grams
  • Latency: About 10ms
  • Dimensions without lens Gear: 51mmx89mmx25mm
  • Resolution: 11 bit, 2000 counts per rev, 0.18 degrees (with gear) can be increased to 0.08 degrees
  • Power: 5V 500mA
  • Port: USB type C
  • Spindle diameter: 6mm
  • Material: PA12 Nylon