Capacitive touch screens continue to evolve with the diversification of electronic devices, such as use in harsh environments, support for large displays, and support for various shapes such as curved surfaces.
Capacitive touch screens use the weak capacitance change of just a few pF between the finger and the sensor as a signal. Because the signal is so small, external noise from interference such as water droplets and gloves can cause malfunctions.
NISSHA has developed a capacitive touch screen that can be operated accurately even in such a noisy environment by improving the following three points.
NISSHA’s original film double-sided simultaneous patterning technology has realized a more precise sensor arrangement with a small tolerance of X and Y electrode positions. As a result, the variation between individual sensors has been reduced, and the controller IC can be tuned more severely.
By lowering the resistance of the ITO of the electrode material, the influence of noise has been reduced.
By lowering the resistance of the ITO electrode, the change in the current signal when the panel is touched with a finger becomes large. As the signal value increases, it becomes less susceptible to noise.
The characteristics of a capacitive touch screen have many factors that are determined by the controller IC. NISSHA has accumulated know-how to select the most suitable IC according to the customer’s application.
There is an increasing need for “hover input,” an operation technology that allows input without touching the panel, in applications such as medical sites and digital signage.
The capacitive touch screen does not detect when the finger touch on the panel, but detects the change in capacitance between the finger and the sensor. Therefore, by detecting the finger that are higher than touching the panel, contactless input is possible.
NISSHA is developing a capacitive touch screen that supports hover input by adopting a low-resistance conductive pattern and optimizing the controller IC.
Operable distance between fingertip and sensor : about 50 mm
Can be used in such situations
Sites with strict hygiene management
medical sites, food factories, shops, etc.
Public facilities handled by an unspecified number of people
Digital signage
automatic ticket vending machines, ATMs, etc.
Products that dislike fingerprint contamination品
TVs, mobile devices, etc.
The capacitance type touch screen detects the change in capacitance between the fingertip and the sensor as an input signal. Therefore, if the surface of the panel is wet with a conductive liquid such as oil or water, the capacitance generated by the liquid becomes a large noise, and there is a problem that the input signal from the finger cannot be detected.
Function to prevent erroneous input due to water droplets : Up to 10cc of water droplets, erroneous input / erroneous reaction due to the capacitance of water droplets is prevented.
Operation when water droplets adhere: Even if 10cc of water droplets adhere to the panel surface, it can be operated without problems in other areas.
Also, if it is a small amount of water droplets, it is possible to input through the water droplets.
The touch panel, which is resistant to water droplets, can be used not only outdoors and at leisure, but also for industrial purposes with peace of mind.
Can be used in such situations
Outdoor use：humid and dew condensation areas such as rainy weather and snowfall areas
Industrial：refrigerated warehouses, greenhouses, outdoor work sites
Leisure Use：Use in sea, rivers and snowy mountains For outdoor sports such as bicycles, bikes, skis and snowboards
Gloves are made of insulation such as rubber or textile cloth. If you wear gloves and touch the touch screen, the input signal will be weakened due to the increased distance of the insulator between your finger and the sensor.
Input is possible by wearing rubber gloves up to 2 mm thick. We have confirmed that even cloth gloves can be operated up to a thickness of 1.5 mm. It can also be operated with nitrile gloves used in factories.
The touch panel that can be operated while wearing gloves can be operated with confidence not only for industrial use but also for medical use and cold regions.
Can be used in such situations
In the medical field：operation of medical equipment while wearing the rubber gloves
industry, such as factory：operation of the equipment in such as manufacturing site,operation of the information terminal in such cold storage
in cold climates of outdoor use：operation of the information terminals in a state where the gloves
A stylus pen is used on tablet devices used in the field of illustration creation. Since the contact area between the tip of the stylus pen and the panel of the tablet terminal is very small, there is a problem that the input signal becomes small in the capacitive touch screen and it is easily affected by noise.
In NISSHA’s capacitive touch screen, the weak signal of the pen tip is increased by lowering the resistance of the sensor electrode and optimizing the IC, making it less susceptible to noise.
In addition, the sensor pattern with a line width of 10 μm formed by photo-etching realizes a higher-density sensor array than the conventional capacitive touch screen. Even the delicate designs that users draw on the panel can be faithfully drawn.
The pen is compatible with active stylus and passive stylus.
Can be used for such purposes
Tablets for drawing illustrations, manga, anime, etc., electronic blackboards
Operation through the cover panel, which reduces the input signal, was an issue for capacitive touch screens. The cover panel of the plastic molded product has a thickness of about 1 to 2 mm. As a result, the distance between the operating finger and the sensor increases, and the change in capacitance becomes small.
NISSHA has overcome this problem by using fine patterning technology for low-resistance ITO thin films and optimizing controller ICs.
NISSHA supports not only touch screen modules that are attached to glass panels, but also housing modules that have a touch screen attached to the display window of plastic molded products.
Can be used for such purposes
In-vehicle display (CID), operation panel of electrical appliances
A high resistance ITO with a resistance value of about 150Ω was used for the sensor electrode of the conventional capacitive touch screen. ITO with a high resistance value has a problem that the response speed becomes slower as the area of the touch screen becomes larger.
NISSHA is working on the development of new conductive materials that solve these problems, and is expanding the applications of capacitive touch screens.
As displays become larger, there is an increasing need for touch screens to support them. However, with a capacitive touch screen that uses ITO as the sensor pattern, there is a problem that the response speed is slow due to the high resistance value of ITO, and it was difficult to increase the area.
Also, the mask size used for patterning was not available for a large area.
Therefore, Cu mesh electrodes are used for large-area touch screens, but Cu mesh has problems such as light transmittance and the mesh sensor being visible.
NISSHA has solved the problem of increasing the area of the touch screen by developing a conductive material with low resistance and excellent permeability, and establishing a patterning technology by connecting multiple touch screens.
Conductive material
Low resistance ITO: Sheet resistance 150Ω / □ → 70Ω / □
Patterning by connecting multiple chomes
Can process up to 500mm * 1000mm sheet size
Utilizing this technology, we have succeeded in developing a capacitive touch screen up to 32 inches.
Can be used for such purposes
Large Display
Electronic Blackboard
Digital Signage
NISSHA accepts the production of custom products according to customer’s request.
Please feel free to contact us using the inquiry form.
We can undertake from material selection to production according to the specifications received from the customer.
From the manufacture of film sensors to the cover panel bonding module, we will deliver in the product form according to your request.
Please feel free to contact us for any questions or consultations on film devices, including consultation on development, trial production, mass production consignment, etc.
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