Light engine and projection device

A projection device, comprising:

• a light engine, comprising:
• a housing;
• an optical assembly comprising a light source and a light converging member, a first lens, a liquid crystal light valve, and a second lens arranged in sequence along a propagation path of light emitted from the light source, wherein the first lens, the second lens, and the housing cooperatively define a first closed chamber, the first closed chamber comprises an air-cooling chamber, a first heat exchange chamber, and a second heat exchange chamber, the first heat exchange chamber and the second heat exchange chamber are arranged on opposite sides of the light converging member, respectively, the air-cooling chamber is arranged between the first heat exchange chamber and the second heat exchange chamber and is in communication with the first heat exchange chamber and the second heat exchange chamber, respectively, the liquid crystal light valve is arranged in the air-cooling chamber;
• a heat exchange device provided on a wall of the first heat exchange chamber and/or a wall of the second heat exchange chamber, and a part of the heat exchange device being located in the first heat exchange chamber and/or the second heat exchange chamber;
• and
• an air blower provided in the first heat exchange chamber or the second heat exchange chamber, wherein the air blower is configured to circulate cooling airflow in the first heat exchange chamber, the air-cooling chamber, and the second heat exchange chamber and enable the cooling airflow to flow through the liquid crystal light valve and the heat exchange device,
• wherein a first air channel is formed between the first lens and the liquid crystal light valve, a second air channel is formed between the liquid crystal light valve and the second lens, one end of the first air channel is in communication with one end of the second air channel through the first heat exchange chamber, the other end of the second air channel is in communication with the other end of the first air channel through the second heat exchange chamber, the air blower is located in the second heat exchange chamber, the air blower is provided with an air inlet and an air outlet, the air outlet is in communication with the first air channel, and the air inlet is in communication with the second air channel.