OKS3604-A4-650 170 Degree Ultra Wide M12 Lens Case: Low Vignetting 2MP Imaging for Smart Vending Machines
Project Background
Smart vending machines are no longer simple dispensing units. Modern retail deployments combine product recognition, transaction verification, theft deterrence and remote shelf monitoring in a single enclosure. Every one of these functions depends on the machine's camera module, and therefore on the lens behind it.
A vending machine integrator required an ultra-wide M12 lens that could keep the full cabinet front, the payment area and the customer's hand position in frame from a single camera mounted inside a shallow door panel. After comparative testing, the OKS3604-A4-650 170-degree ultra-wide M12 lens was selected for production.
Challenges in Vending Machine Imaging
- Narrow field of view: lenses below 140 degrees could not cover both the payment terminal and the product drop zone, forcing integrators to add a second camera.
- Dark corners: low-cost wide-angle optics produced heavy vignetting, so product barcodes and labels near the frame edge became unreadable for recognition algorithms.
- Depth of field limitations: customers operate at 20-60cm from the panel while the interior shelf sits further back, requiring sharp focus across a wide range.
- Colour shift under mixed light: LED shelf lighting plus outdoor ambient light caused colour casts that reduced recognition accuracy.
- Space and weight budget: the door panel leaves only millimetres for the camera module and cannot carry a heavy lens assembly.
Selected Optical Solution
The OKS3604-A4-650 uses a compact 2G4P all-glass construction with a 650nm IR cut filter, a 1.98mm focal length and a 170-degree diagonal field of view. The 13.4mm-class barrel and standard M12x0.5 mount fit the integrator's existing door-mounted module without mechanical redesign.
| Parameter | Specification |
|---|---|
| Model | OKS3604-A4-650 |
| Focal Length | 1.98mm |
| Field of View (1/2.7'') | H: 160° / V: 96° / D: 175° |
| Resolution | 2MP / 1080P |
| Relative Illumination | 55% (low vignetting) |
| Lens Structure | 2G4P |
| IR Filter | 650nm IR cut |
| CRA | < 26.9° |
| Mechanical BFL | 2.99mm |
| Optical BFL | 3.89mm |
| Waterproof Level | IP69K |
| Operating Temperature | -40°C to +85°C |
Implementation Process
- Frame coverage mapping: the 160° horizontal view was mapped against the cabinet geometry so that payment keypad, QR scanner and product outlet all fall inside the usable image area.
- Vignetting calibration: the 55% relative illumination kept edge brightness high enough for consistent barcode decoding without software gain compensation.
- Sensor matching: the CRA below 26.9° and 6.8mm image circle were verified against a 1/2.7'' 2MP sensor for edge sharpness and colour uniformity.
- Focus setting: the lens was focused at the customer interaction plane to keep both the payment zone and interior shelves acceptable across the working range.
- Reliability validation: samples passed IP69K washdown, thermal cycling from -40°C to +85°C, and vibration testing before mass production release.
Project Results
| Metric | Before | After |
|---|---|---|
| Cameras per machine front | 2 units (narrow lens) | 1 unit (170° lens) |
| Usable coverage | Payment area only | Full cabinet front + payment zone |
| Edge barcode readability | Frequent failures | Consistent decoding |
| Colour accuracy | Cast under mixed light | 650nm IR cut, true-to-life colour |
| Field failures | Dust and moisture ingress | IP69K sealed assembly |
With one 170-degree lens per machine, the integrator removed a second camera module from each door panel. This reduced wiring, assembly time and calibration steps, while the low-vignetting image improved recognition stability at the edge of the frame where customers hold products and phones.
Why This Lens Suits Smart Retail Hardware
- One camera, whole front panel: 170-degree diagonal coverage replaces dual-camera setups in compact doors.
- Low vignetting optics: 55% relative illumination keeps corner detail usable for barcode and QR recognition.
- Compact and light: small barrel and low weight suit slim vending machine door modules and doorbell-style housings.
- Stable colour: integrated 650nm IR cut filter restores natural colour under LED and ambient lighting.
- Built for outdoors: IP69K sealing and a -40°C to +85°C range cover semi-outdoor and unheated installations.
- Mass-production ready: M12x0.5 thread supports automated assembly and consistent focus setting.
Conclusion
The OKS3604-A4-650 gave this smart vending programme a single-lens solution covering payment verification, product recognition and anti-theft monitoring, cutting hardware count while improving image reliability at the frame edge. The same platform is available for video doorbells, access control readers, retail people-counting cameras and other compact wide-angle modules.
Contact our optical engineering team for samples, datasheets, or a customised FOV and CRA specification for your vending and retail hardware design.
