Client Background

A well-known European home appliance brand, with products sold across 40+ countries, was developing a flagship smart kitchen range hood targeting the premium segment. The design brief called for a seamless, minimalist user interface — no mechanical buttons, no visible bezels — relying entirely on touch interaction through a flush glass surface. The client had previously worked with Asian touch panel suppliers but experienced inconsistent quality, long lead times, and poor responsiveness to design changes.

SanTeXing was introduced through a TDK sourcing contact (one of SanTeXing's long-standing partners). After an initial technical audit of our Xiamen production facility, the client awarded us the development contract for the touch control module.

The Challenge

The kitchen environment is uniquely demanding for touch interfaces:

• Grease and moisture: Cooking vapors create a continuous film of oil and condensation on the touch surface, which can cause false touches or desensitize standard capacitive sensors.
• Glove operation: Users often operate the hood while wearing kitchen gloves. The touch panel must reliably detect touches through latex, nitrile, or silicone gloves up to 1.5 mm thick.
• Heat exposure: The panel sits directly above cooking surfaces and must withstand ambient temperatures up to 85°C without degradation in touch sensitivity or optical clarity.
• Design aesthetics: The glass panel must be completely flat with no visible buttons when idle — icons only illuminate upon approach — and support swipe gestures for fan speed adjustment and brightness control.
• Regulatory: CE, UKCA, and EN 60335 household appliance safety certification required.

Our Solution

SanTeXing developed a complete turnkey touch control module combining a projected capacitive (PCAP) touch sensor bonded to a tempered glass cover lens, with custom firmware and LED backlighting:

1. High-Sensitivity PCAP Sensor

The touch sensor was designed with a 16 × 10 diamond-pattern ITO electrode matrix on a 0.7 mm soda-lime glass substrate. Mutual-capacitance scanning at 120 Hz enables reliable touch detection even through grease film and gloves up to 1.5 mm thick. The signal-to-noise ratio exceeds 60:1, well above the 40:1 minimum required for kitchen environments.

2. Proximity Wake Feature

We implemented a low-power proximity detection mode using self-capacitance on the outer electrode rows. When the user's hand approaches within 10 cm, the panel wakes from sleep (20 µA standby) to active mode (15 mA), illuminating the icon backlighting. This feature is critical to the "invisible UI" design language — no visible markings when the hood is off.

3. Gesture Recognition

Custom firmware processes touch data to recognize four gestures: tap (on/off), swipe up/down (fan speed 1–6), swipe left/right (light brightness and color temperature), and long-press (boost mode for 10 minutes). The gesture engine uses a simple state-machine algorithm running on the client's main MCU, communicating via I²C at 400 kHz.

4. Environmental Protection

The front face achieves IP65 protection through perimeter adhesive sealing between the glass lens and the housing bezel. A hydrophobic oleophobic coating on the glass surface minimizes oil adhesion and makes cleaning easier. The ITO sensor layer is protected by a passivation coating that prevents galvanic corrosion from condensation exposure.

Results

The touch panel module completed certification testing in 14 weeks from project kickoff, with the following outcomes:

• First-article approval achieved in a single design iteration — no major re-spin required.
• Production ramp to 5,000 units/month within 8 weeks of approval.
• Field return rate < 0.2% after 9 months of European retail availability (approximately 45,000 units shipped as of Q2 2026).
• Consumer reviews consistently highlight the "responsive touch" and "premium feel" of the control interface.
• The client has since awarded SanTeXing two additional touch panel projects for their oven and induction cooktop product lines.

Related Products

This project used SanTeXing's custom touch screen manufacturing capabilities. Explore our IMD panel decoration and membrane switch solutions for appliance control interfaces.