JPH0451129A - Projection type video display device - Google Patents

Abstract

PURPOSE:To perfectly convert a color temperature with simple constitution by providing a color temperature variable filter which can be attached to/ detached from the front surface of the projecting lens of a projector and attaching it according to the preference of a user. CONSTITUTION:The color temperature variable filter 3 is attached to the front surface of the projecting lens 2 by forming a cylindrical part 3b holding a filter part 3a in a lens cap shape. The filter part 3a is a dichroic filter made of inorganic material and the transmissivity of light is different according to wavelength. By attaching the filter 3, the specified wavelength component of projected video light outputted from the lens 2 is attenuated, so that the color temperature of the projected video is converted. Thus, the device complies with various preferences of the users.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a projection type image display device.

[Summary of the Invention] The projection type image display device of the present invention is provided with a removable color temperature variable filter on the front surface of a projection lens that outputs a screen projected image, and the user can adjust the color temperature variable filter according to his/her preference. Attachment to Projection Lens [Problem to be Solved by the Invention] However, in conventional normal projectors, there is a problem in that the user cannot easily change the color temperature of the projected image according to his preference.

Of course, electrical processing (
For example, by increasing the gain of only the B signal among R, G, and B video signals to increase the color temperature, etc., and configuring a projector with an adjustment volume, the user can adjust the image quality. Although it is possible to convert the color temperature, in this case, it is difficult to control color temperature changes because the actual output color image light is not processed. It is not possible to completely match the color temperature of Further, the signal processing circuit becomes complicated and the cost increases, which is not preferable.

[Means for Solving the Problems] The present invention has been made in view of the above problems, and includes a removable color temperature variable filter provided in front of the projection lens of the projector, which the user can use. By wearing it according to your preference, you can change the color temperature of the projected image.

[Function] Since the color temperature can be converted simply by installing a color temperature variable filter, the entire video signal circuit system can remain as it was before, and the color temperature conversion operation is extremely easy and easy to understand for the user. Become.

[Embodiment] FIG. 1 is a perspective view showing an embodiment of the projector of the present invention, where 1 is a front projection type projector main body, and 2 is a projection lens for projecting a screen image.

Reference numeral 3 designates a color temperature variable filter, which can be attached to the front surface of the projection lens 2 by having a cylindrical portion 3b holding a filter portion 3a formed in the shape of a lens cap. The filter section 3a is a guichroic filter made of an inorganic material, and the transmittance of light varies depending on the wavelength.

In addition, as the material of the filter part 3a, organic type,
Various inorganic types can be considered.

In this embodiment, by attaching the variable color temperature filter 3, a predetermined wavelength component of the projected image light output from the projection lens 2 is attenuated, and therefore the color temperature of the projected image can be changed.

Further, by preparing a plurality of color temperature variable filters 3 each having a different wavelength-transmittance characteristic, it is possible to accommodate various user preferences.

FIG. 2 shows another embodiment of the present invention, which is a type of projector that combines output lights from three units of projection lenses on a screen to produce a color image.

In this case, three color temperature variable filters with different filter characteristics are provided, and a projection lens 2 that outputs R, G, and B8 light is provided.
You can set your favorite color temperature by changing the colors of R, 2G, and 2B. Of course, the color temperature of the projected image can be changed by simply attaching the variable color temperature filter 3 to only a specific projection lens. Moreover, if a large number of color temperature variable filters with various characteristics are prepared, a variety of color temperature conversions can be performed.

In the above embodiment, since the variable color temperature filter 3 processes the actual output projection light, a specific color temperature corresponding to the variable color temperature filter can be completely set, and the image Unlike the case where the color temperature is changed by electrically processing the signal, control to obtain a predetermined color temperature is not difficult.

[Effects of the Invention] As explained above, in the projection type image display device of the present invention, the color temperature of the projected image can be controlled simply by installing a color temperature variable filter, and complete color temperature conversion can be easily performed with a simple configuration. It has the effect of being able to

[Brief explanation of drawings]

FIG. 1 is a perspective view showing one embodiment of the invention, and FIG. 2 is a perspective view showing another embodiment of the invention. 1 is a projector body, 2 is a projection lens, and 3 is a variable color temperature filter.

Claims (1)

[Claims] 1 removable color temperature variable filter on the front of the projection lens
Alternatively, a projection type image display device characterized in that the color temperature of a projected image can be changed by providing a plurality of color temperature variable filters.