---
created: 2026-07-07 22:05
modified: 2026-07-07 22:05
type: note
tags:
  - business
aliases: []
---
# [[Digital Binoculars]]


# DIY Face-Mounted Digital HDMI Viewfinder (Obsidian Technical Note)

- **Date:** 2026-07-07
- **Project Type:** Hardware Fabrication / Near-to-Eye (NTE) Display Assembly
- **Objective:** Create a direct, zero-latency digital viewfinder using a 2K LCD screen over HDMI from a digital camera with optical zoom, bypassing all wireless hardware.

---

## 🛠️ Step 1: Optical Procurement (AliExpress)

Do not use basic magnifying glasses or generic Google Cardboard lenses. A high-density 2K display requires specialized optics to prevent warping and extreme chromatic aberration. 

### AliExpress Search Targets
* **Search Query 1:** `50mm Aspheric PMMA Lens FPV`
* **Search Query 2:** `40mm Bi-Convex VR Lens`
* **Search Query 3:** `Phone VR Headset Replacement Lenses`

### Optical Specifications Needed
* **Lens Material:** Aspheric or Bi-Convex PMMA (acrylic) or optical glass. Aspheric is highly preferred for 2K resolution to keep edge-to-edge clarity sharp.
* **Target Focal Length:** Between **45mm and 60mm**. This keeps the physical depth of your 3D-printed housing short, shallow, and lightweight on your face.

---

## 📐 Step 2: Open-Source CAD Data Selection

Instead of designing a facial interface and optical box from scratch, leverage established open-source CAD repositories and upload the `.STL` or `.STEP` files directly to a fabrication service like **PCBWay** or **JLCPCB**.

### Top Repository Recommendations
1. **The "Relativity VR" / DIY_VR Platform (Recommended for Makers)**
   * **Source:** Search GitHub for the `dmcke5 DIY_VR` repository.
   * **Why it fits:** It is an open-source project explicitly designed for makers building low-cost, high-resolution HDMI headsets using AliExpress screens. The "Eyebox" pieces are engineered to mount dual lenses at an exact sliding focal distance right in front of compact LCD panels.
2. **The OpenIPC "PixelPilot" Shell**
   * **Source:** Search Printables or Thingiverse for `OpenIPC PixelPilot Goggle Body`.
   * **Why it fits:** This is a field-tested, modern shell designed to hold small, high-density displays. It includes mechanical sliders so you can adjust your **IPD (Interpupillary Distance)** manually.

---

## 🏭 Step 3: Manufacturing Configuration (PCBWay / JLCPCB)

When configuring your order on a 3D printing platform, use these specific parameters to ensure the build survives active use:

| Component / Section | Recommended Material | Print Technology | Reason |
| :--- | :--- | :--- | :--- |
| **Main Goggle Body / Face Plate** | **Nylon (PA12)** or **PETG** | **SLS** (Selective Laser Sintering) | Provides durable, impact-resistant structures that won't warp under outdoor heat. |
| **Internal Lens Holders & Mounts** | **Matte Black Resin** or **Matte PLA** | **SLA** (Stereolithography) or FDM | **Crucial:** Matte black prevents internal light bounce and reflections into your eyes. |

---

## 🔌 Step 4: Hardware Architecture & Wiring Pipeline

Because you are bypassing wireless modules entirely, your minimal hardware pipeline is streamlined for zero latency:
[Digital Camera]│ (Clean HDMI Output @ 60fps)▼[Flexible HDMI Cable]│▼[Display Driver Board (Mounted to Shell/Strap)]│ (FPC Ribbon Cable)▼[2K LCD Screen] ───> [Aspheric Lenses] ───> [User Eyes]
### Critical Rules for the Build
1. **Clean HDMI Output:** Ensure your camera supports "Clean HDMI" (sends the video feed without on-screen battery icons or menu text). 
2. **The Diopter Constraint:** You cannot look directly at micro-displays without optics. The shell must house your sourced lenses at an exact distance matching their focal length ($f \approx d_o$) so your eyes can focus effortlessly.
3. **Power Delivery:** Tie a portable USB power bank to the display driver board via a simple USB-C cable or 5V DC step-down regulator.

---


### 1. The Displays & Driver (AliExpress / eBay) * 

**Sourced Module:** `Wisecoco 2.9 Inch 1440x1440 Dual LCD Display Screen Kit` (Model: Sharp LS029B3SX02). * **Included Hardware:** 2x 2.9" Square LCD Panels (with backlights) + 1x Dual MIPI HDMI Driver Board. * **Interface:** Single Full-Size HDMI Input / Powered via 5V Micro-USB or USB-C.


# SECOND APPROACH


# Stadium Viewfinder Goggles (Commercial MVP Technical Note)

- **Date:** 2026-07-07
- **Project Type:** Hardware Fabrication / Commercial Product Blueprint
- **Objective:** Create a direct, zero-latency stadium viewfinder using a high-brightness 5-inch 1080p display over HDMI from a 5x optical zoom camera. This setup provides an affordable, wide-angle cinematic view for live sports and concerts without complex wireless hardware or dual-screen software splitting.

---

## 🛠️ Step 1: Optical Sourcing & Selection (AliExpress)

To ensure this product is low-cost and easy for users to look into, the architecture relies on a single-screen "box goggle" configuration. This layout uses one shared lens instead of separate eyepieces.

### AliExpress Search Targets
* **Search Query 1:** `5 inch FPV box goggle replacement Fresnel lens`
* **Search Query 2:** `3x magnification PVC Fresnel lens sheet`
* **Search Query 3:** `Credit card magnifier Fresnel lens 3x`

### Optical Specifications Needed
* **Lens Material:** Optical-grade Acrylic or PVC Fresnel sheet.
* **Magnification Factor:** 3x magnification.
* **Target Profile:** Flat, ultra-lightweight rectangular sheet cut to fit the internal width of the goggle shell (~120mm x 70mm). This configuration allows both eyes to focus on a single large canvas simultaneously, preventing double vision.

---

## 📐 Step 2: Open-Source CAD Data Selection

Instead of designing a facial interface and optical box from scratch, leverage established open-source CAD repositories for box goggles and upload the `.STL` or `.STEP` files directly to a fabrication service like **PCBWay** or **JLCPCB**.

### Top Repository Recommendations
1. **The Eachine EV800 / EV800D Open Source Shell**
   * **Source:** Search Thingiverse or Printables for `Eachine EV800 Upgrade Shell` or `DIY FPV Box Goggle Case`.
   * **Why it fits:** This form factor is explicitly engineered for a single 5-inch screen and a front-mounted rectangular Fresnel lens. It offers excellent ergonomics and safely clears eyeglasses.
2. **The Quanum DIY FPV Goggle V2 Chassis**
   * **Source:** Search GrabCAD or Thingiverse for `Quanum DIY Goggle V2`.
   * **Why it fits:** A classic, deep-box layout that provides the exact focal distance required to focus comfortably on a 5-inch panel without eye strain.

---

## 🏭 Step 3: Manufacturing Configuration (PCBWay / JLCPCB)

When configuring your production order on a 3D printing platform, use these specific parameters to ensure the product survives outdoor stadium environments:

| Component / Section | Recommended Material | Print Technology | Reason |
| :--- | :--- | :--- | :--- |
| **Main Goggle Body / Face Plate** | **Nylon (PA12)** or **PETG** | **SLS** (Selective Laser Sintering) | Provides durable, impact-resistant structures that won't warp under outdoor stadium heat. |
| **Internal Lens Grooves & Mask** | **Matte Black Resin** or **Matte PLA** | **SLA** (Stereolithography) or FDM | **Crucial:** Matte black absorbs light bounce, stopping daylight reflections from washing out the screen. |

---

## 🔌 Step 4: Hardware Architecture & Sourcing Checklist

This pipeline bypasses wireless modules and Raspberry Pi video processing, achieving direct hardware compilation with absolute zero latency.

### Sourcing Specifications
* **Display Module:** `5.0 Inch 1080p HDMI LCD Monitor Module with Backlight` (Ensure it is rated for **800 to 1000 nits** of brightness for daylight visibility).
* **Camera Module:** `5x Optical Zoom Camera Block with HDMI Output` (Provides stable tracking that matches natural human head movement limits of 90°–120°/sec).

### System Diagram

```

Use code with caution.

[ Front Brim Mounted 5x Zoom Camera ]  
│  
▼ (Direct Hardware Micro-HDMI to HDMI Cable)  
┌───────────────────────────────────────────────────────────┐  
│ [ 5-Inch High-Bright HDMI LCD Panel ] │  
│ (Built-in Backlight, Powered via 5V USB) │  
└───────────────────────────────────────────────────────────┘  
│  
▼ (Image cast across full screen canvas)  
[ Single Rectangular 3x Fresnel Lens Sheet ]  
│  
▼  
[ User Vision ] (Immersive, wide-angle stadium view)

```

### Critical Rules for Commercial Assembly
1. **The Focal Alignment Rule ($f \approx d_o$):** The single Fresnel lens sheet must be positioned inside the internal shell slots at the exact distance where the 5-inch screen drops into perfect focus for the average user (typically 65mm–85mm from the eye line).
2. **Clean HDMI Output:** Ensure the 5x camera block firmware is set to output a clean video signal without battery icons, crosshairs, or settings overlays showing up on the user's screen.
3. **Power Delivery Integration:** Power the display driver board via a standard 5V USB-C tether line running to a pocket-sized portable power bank. Trigger the camera's zoom motor using a hand-held remote control containing a simple, mechanical rocker switch.