EMC & EMI Shielding Solution

What is the difference between an EMI wave absorber and EMI shielding tape?

Wave absorbers (AS-EM series) work by absorbing electromagnetic energy within the material itself — they convert incoming EMI into heat rather than reflecting it. This makes them the correct choice when reflection would cause additional interference, such as near loop antennas or NFC modules. Shielding tapes (copper, AL+PET, conductive fabric) reflect and redirect EMI through a conductive barrier — they are used for enclosure grounding, cable wrapping, and path-to-ground connections. In most device assemblies, both types are used together: absorbers to manage near-field noise sources, shielding tapes to establish the conductive enclosure and grounding continuity.

What frequency range do the AS-EM wave absorbers cover?

The AS-EM series is rated for 100 MHz to 6 GHz. This covers the primary operating frequencies of modern consumer electronics, wireless communication modules (Wi-Fi, Bluetooth, cellular), and NFC/RFID systems. The absorber thickness (50–350 μm) and magnetic metal powder loading are tuned to target peak absorption within specific sub-bands — contact us with your frequency range and we can confirm which AS-EM grade is optimized for your application.

How do I choose between copper conductive tape (AS-CC) and conductive fabric (AS-CF)?

Choose copper tape (AS-CC) when you need low surface resistance (as low as 0.05 Ω) with high adhesion (up to 1500 gf/25mm) — typical for printed circuit board grounding pads, rigid enclosure grounding strips, and cable shielding where secure bond strength matters. Choose conductive fabric (AS-CF) when flexibility is the primary requirement — the fabric construction stretches and bends without cracking the conductive layer, making it the correct choice for cable wrap, flexible gaskets, and assemblies that require repeated flexing. AL+PET tape (AS-CPA) falls between the two: 60 μm thin and 0.2 Ω surface resistance, suited for lightweight device constructions where copper tape is too rigid or thick.

Can EMC shielding materials be die-cut to custom shapes and sizes?

Yes. Conductive tapes, wave absorber sheets, and conductive foam can all be precision die-cut to custom geometries including rings, frames, slots, and complex shield profiles. ALS Tape supports both soft-tooling for prototype quantities and hard-tooling for production volumes. Typical dimensional tolerance is ±0.2 mm for conductive tape and foam materials. Provide a DWG, DXF, or dimensioned drawing and we will confirm feasibility and tooling lead time.

What is the light-blocking performance of the display shielding tape?

The display shielding tape achieves greater than 99.9% light blocking in both Black & Black and White & Black configurations. Black & Black (both sides dark) is used for light leakage prevention at display module edges and between panel layers. White & Black (white reflective top, black base) is used in backlight units (BLU) to enhance light reflection efficiency while maintaining light isolation on the shielding side. Both configurations also provide electrical insulation and high thermal stability for display assembly environments.

What industries and applications use your EMC shielding solutions?

Primary applications are in consumer electronics (smartphones, tablets, laptops), communication equipment (base station modules, wireless devices), automotive electronics (infotainment, ADAS control units, EV BMS), display module assembly (LCD, OLED), and industrial control equipment. EMC compliance testing (FCC, CE, VCCI) drives demand in all of these sectors — the wave absorbers and shielding tapes are typically specified at the PCB and module level to achieve pass rates and reduce re-test cycles.

How does conductive foam differ from standard closed-cell foam tape for device sealing?

Standard foam tape provides mechanical sealing only — it fills gaps and blocks dust and moisture but provides no electrical function. Conductive foam (urethane base + base film + acrylic adhesive) provides both compression sealing and electrical conductivity, allowing the foam gasket to simultaneously seal the enclosure and create a grounded conductive path across the joint. This is critical in devices where the internal shield compartments must maintain electrical continuity at the enclosure seam to meet EMC requirements.