Camera lens for digital projector

Abstract

The invention discloses a camera lens for a digital projector. The camera lens comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, a seven lens, an eighth lens, and a ninth lens, along an optical axis from the object plane to the image plane. An aperture diaphragm is arranged between the fourth lens and the fifth lens and is close to the fifth lens. Through the image space telecentric light path, CRA is controlled to be matched with the lighting system within a certain range so as to realize distinct image contrast and high energy utilization. The first lens and the eighth lens close to the screen are aspheric, the first lens is aspheric and used for correcting various monochromic aberrations and distortion of the field outside the axis, and the eighth lens is used for correcting various monochromic aberrations on the axis.

Description

technical field [0001] The invention relates to a lens, in particular to a lens for a digital projector. Background technique [0002] With the development of semiconductor technology in recent years, the projection display industry based on technologies such as DLP (Digital Light Processing: Digital Light Processing), LCD (Liquid Crystal Display: Liquid Crystal Display), and LCOS (Liquid Crystalon Silicon: Liquid Crystal on Silicon) has developed rapidly. Over the years, DLP projection display technology has developed rapidly with its rich colors, high-definition images, high-brightness images and high-contrast displays. It can achieve smaller and lighter product features, so DLP (Digital Light Processing : digital light processing) miniature projectors have also obtained rapid development. The core component of DLP (Digital Light Processing: Digital Light Processing) technology mainly adopts DMD (Digital Micromirror Device: Digital Micro Mirror) image chip. DMD (Digital M...

AI Technical Summary

Problems solved by technology

In addition, since DLP (Digital Light Processing: digital light processing), LCOS (Liquid Crystalon Silicon: liquid crystal on silicon) or LCD (Liquid Crystal Display: liquid crystal display) systems will use TIR (total internal reflection: total internal reflection) or PBS (polarization beam splitter polarization beam splitter prism) prism to To achieve effective lighting, therefore, the projection lens needs to retain a long rear working distance when matching it, which greatly increases the difficulty of controlling the length of the lens and off-axis aberration. The measure is generally to increase the number of lenses, generally more than ten pieces As a result, the lens becomes complex, and when the field of view increases, there will be obvious distortion

Through investigation, it is not difficult to find that some projector lenses on the market generally have shortcomings such as large size, low image quality, and small field of view.

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