The development of the tungsten wire industry has been closely linked with the lighting bulb industry from the beginning. In 1878, Edison invented the carbon filament lamp, but it has serious drawbacks that mainly short life. Nearly 20 years later (1897), the carbon filament was replaced by osmium wire and tantalum wire. However, because the melting point of Os and Ta is low, the working temperature and light efficiency are low.

In 1879, Edison tried carbon filament for hundreds of hours. Although carbon has a high melting point, it has a low sublimation temperature. It sublimates directly from solid to gas at low temperature, so it is easy to consume and has a short service life. At present, almost all of the bulbs are used tungsten wire with the melting point of 3410 , the advantage of which is that the sublimation rate is lower when the temperature is lower than the melting point, so it can be heated to a higher temperature than the carbon filament. The tungsten wire also burns in the air, so the bulb needs to be pumped into a vacuum.

To prevent the filament from sublimating, the bulb was filled with inert gases, which are mainly argon and do not contain oxygen, allowing partially vaporized tungsten atoms to return to the filament through collisions. Although the inert gas has increased the filament's service life, however, due to the existence of inert gas in the original vacuum bulb, the heat conduction and convection are increased, the energy is taken away and the equilibrium temperature is reduced, and the faint particles formed by sublimated tungsten gas in the inert gas also form black spots on the inner surface of the bulb by convection.

Hungary made its first tungsten wire in 1903, under the patents of A. Just and FHannaman. The tungsten wire is made by heating the carbon filament to a high temperature by electric current in a halogen oxide vapor containing free hydrogen tungsten, which is completely replaced by tungsten. The resulting incandescent filament contains more or less carbon, which is not only brittle but also compacted when used, so the electric parameters of the filament will change.

Advanced Refractory Metals (ARM) supplies people with high-quality tungsten products, including tungsten wire, tungsten powder, etc. all over the world. Please visit https://www.refractorymetal.org for more information.

Molybdenum oxide (also known as molybdenum trioxide) is a colorless or yellowish-white powder, which soluble in water slightly and soluble in acid, alkali, and ammonia solution completely.

Molybdenum oxide layer has been widely used in the modern graphic screen because of its low optical reflective, no matter it is reliable for subpixel separation, or a way of covering conductors with or prevent unnecessary reflection from ambient light.

Narrow frame display: covers the conductor

Modern desktop monitors and large TV screen abandoned plastic edge (narrow) framework, which not only improved the appearance, also made the condition of a few screens together to form a large screen come true. But the high reflection molybdenum, aluminum or copper conductor on the TFT glass will be exposed when there is no plastic frame. Molybdenum oxide antireflective coating solved this problem, it will reflect less than 6% of the incident light (550 nm), so as to make the conductor invisible.

OLED: a collection of reflector and electrode resistance

TFT metal molybdenum layer (the source/drain) reflects the ambient light falling on the OLED display so as to reduce the contrast of the monitor. A circular polarizing filter like this used to reduce unnecessary reflection. Although the reflection from the electrode reduced, the light output of the monitor also reduced. So molybdenum oxide is the ideal of TFT substrate metallization of reflector since it absorbs light very well, and it is also an electrical conductor.

The metal molybdenum can reflect about 60% of the incident lights; this value is greater than 6% of the same thickness of the molybdenum oxide layer. OLED manufacturers eliminate polarization by using a molybdenum oxide layer.

Touch screen anti-reflective coating

Molybdenum oxide PVD film can prevent unnecessary reflection between the metal surface (metal bridge) with capacitive touch sensors.

Advanced Refractory Metals (ARM) supplies people with high-quality molybdenum products all over the world. Please visit https://www.refractorymetal.org for more information.