CN214623325U

CN214623325U - Holographic projection clock

Info

Publication number: CN214623325U
Application number: CN202121152554.5U
Authority: CN
Inventors: 汪子豪; 汪子杰
Original assignee: Ningbo Qianjie Electronic Technology Co ltd
Current assignee: Ningbo Qianjie Electronic Technology Co ltd
Priority date: 2021-05-27
Filing date: 2021-05-27
Publication date: 2021-11-05
Anticipated expiration: 2031-05-27

Abstract

The utility model discloses a holographic projection clock, the on-line screen storage device comprises a base, the base on be fixed with the imaging screen, the base still be provided with short burnt projection module and holographic projection control circuit, short burnt projection module including light source subassembly, display device, refraction lens group and the aspheric mirror of arranging in proper order, refraction lens group and aspheric mirror constitute projection lens group, the light source subassembly including light-emitting component and condensing lens, holographic projection control circuit with display device signal connection. The utility model has the advantages that: the structure is reasonable, the short-focus projection module is matched with the aspheric reflector, the projection focal length and the reflection imaging range are greatly shortened, the miniaturization of the whole structure of the holographic projection clock is facilitated, and the manufacturing cost is reduced.

Description

Holographic projection clock

Technical Field

The utility model belongs to the technical field of the clock manufacture technique and specifically relates to a holographic projection clock.

Background

With the development of holographic transparent display technology, more and more products are related to the field. Most of the existing holographic projection technologies are realized by projectors and holographic projection film projection, but no scheme for applying the technology to life at low cost is provided. The existing clock transparent display schemes comprise (1) a transparent oled technology, but the cost is high; (2) the projector is used for imaging on the transparent projection film, but the scheme has extremely high cost and cannot be applied to products with lower guest unit price; (3) the scheme of the transparent LCD cannot self-illuminate, the effect is poor, and the transparency is not high.

The patent application with the prior application number of CN201520799138.2 named as 'holographic projection clock' discloses a holographic projection clock, which comprises an installation base with an inner cavity, wherein an opening end of the installation base is provided with an installation cover, a holographic projection circuit board is arranged in the inner cavity of the installation base, a control circuit board and a power circuit, the installation cover is provided with an installation through hole connected with an annular clock frame body on the outer side of the installation cover, the bottom of the annular clock frame body is provided with a projection port for placing a holographic projection lens, an image reflection assembly is circumferentially arranged on the inner side of the annular clock frame body, the holographic projection lens is connected with the holographic projection circuit board, the holographic projection circuit board is connected with the control circuit board, and the control circuit board is connected with the power circuit. However, the structure is complicated and large, and thus the structure is desired to be further improved.

SUMMERY OF THE UTILITY MODEL

The utility model aims to make up the above deficiencies, and discloses a holographic projection clock with reasonable structure, low manufacturing cost and small volume to the society.

The technical scheme of the utility model is realized like this:

the utility model provides a holographic projection clock, including the base, the base on be fixed with the imaging screen, the base still be provided with short burnt projection module and holographic projection control circuit, short burnt projection module including light source subassembly, display device, refraction lens group and the aspherical mirror that arranges in proper order, refraction lens group and aspherical mirror constitute projection lens group, the light source subassembly including light-emitting component and condensing lens, holographic projection control circuit with display device signal connection.

The measures for further optimizing the technical scheme are as follows:

as an improvement, the projection lens group has a throw ratio of 0.35-0.4, a relative illumination greater than 80% and a distortion rate less than 5%.

As an improvement, the refraction lens group includes a first lens, a second lens and a third lens which are arranged in sequence along a common optical axis, the first lens is a biconvex lens or a double-cemented lens, the second lens is a biconvex lens or a double-cemented lens, and the third lens is a negative crescent lens.

As a modification, a diaphragm is arranged between the second lens and the third lens. A stop is provided for limiting the entrance pupil aperture.

As an improvement, the display device is an LCD display or a DMD display chip.

As an improvement, the aspheric surface reflector adopts a concave even-order aspheric surface reflector, and the aspheric surface coefficient of the aspheric surface reflector is not more than 10 orders.

As an improvement, the imaging screen is perpendicular to the base.

As an improvement, the imaging screen is obliquely fixed on the base towards the short-focus projection module side.

Compared with the prior art, the utility model the advantage be:

the holographic projection clock of the utility model has reasonable structure, greatly shortens the projection focal length and the reflection imaging range by utilizing the matching of the short-focus projection module and the aspheric reflector, is beneficial to the miniaturization of the whole structure of the holographic projection clock, and reduces the manufacturing cost; the utility model discloses a holographic projection clock, the light beam that the illuminating part produced form the light beam that is close the parallel through condensing lens, reduces short burnt projection module's entrance pupil diameter, and the light beam is through short burnt projection module's display device, with the display information on the display device through refraction battery of lens to through aspherical mirror reflection imaging on the imaging screen.

Drawings

Fig. 1 is a schematic structural diagram of a first embodiment of the present invention;

fig. 2 is a light path diagram of a refractive lens assembly according to an embodiment of the present invention;

fig. 3 is a projected MTF graph according to an embodiment of the present invention;

fig. 4 is a distortion diagram of a projection according to an embodiment of the present invention;

fig. 5 is a schematic structural diagram of a second embodiment of the present invention;

fig. 6 is a light path diagram of a two-refractive lens assembly according to an embodiment of the present invention;

fig. 7 is a schematic structural diagram of a third embodiment of the present invention.

The utility model discloses each reference numeral's name is in the drawing:

the display device comprises a base 1, an imaging screen 2, a light source component 31, a luminous component 31a, a condensing lens 31b, a display component 32, a refraction lens group 33, a first lens 33a, a second lens 33b, a third lens 33c, a diaphragm 33d and an aspheric reflector 34.

Detailed Description

The present invention is described in further detail below with reference to the attached drawings:

in a first embodiment, as shown in fig. 1 to 4, a holographic projection clock includes a base 1, the base 1 is fixed with an imaging screen 2, the base 1 is further provided with a short-focus projection module and a holographic projection control circuit, the short-focus projection module includes a light source assembly 31, a display device 32, a refraction lens assembly 33 and an aspheric reflector 34, which are sequentially arranged, the refraction lens assembly 33 and the aspheric reflector 34 constitute a projection lens assembly, the light source assembly 31 includes a light emitting element 31a and a condensing lens 31b, and the holographic projection control circuit is in signal connection with the display device 32.

The imaging screen 2 may be made of a transparent material having a certain opacity and a certain haze, such as ground glass, ground acrylic (the haze is close to 100%), or a transparent glass to which a layer of holographic projection film is attached.

The holographic projection control circuit mainly comprises a microcontroller and a single chip microcomputer, wherein the control circuit can select an STM8 microcontroller as a main control chip, and the current time information is acquired through communication of an SPI protocol on a DS1302 clock chip. The LCD driver chip can be HT1621 driver chip. The single chip microcomputer obtains the current time from the DS1302, transmits data to the HT1621 driving chip through a plurality of connected pins in a serial communication mode, controls the display time of the projection LCD screen, and projects the time on the screen through the projection lens.

The light emitting member 31a employs an LED.

The projection lens group has a projection ratio of 0.35-0.4, a relative illumination greater than 80%, and a distortion rate less than 5%. By adopting the projection lens group, the manufacturing cost is low, and the requirement of projection imaging can be met.

The refraction lens group 33 comprises a first lens 33a, a second lens 33b and a third lens 33c which are sequentially arranged along a common optical axis, the first lens 33a is a biconvex lens, the second lens 33b is a biconvex lens, and the third lens 33c is a negative crescent lens.

A diaphragm 33d is disposed between the second lens 33b and the third lens 33 c. The diaphragm 33d is provided for limiting the entrance pupil aperture, further contributing to miniaturization of the overall structure of the holographic projection clock.

The display device 32 is an LCD display. The display device 32 may also employ a DMD display chip here.

The aspheric reflector 34 is a concave even-order aspheric reflector, and the aspheric coefficient of the concave even-order aspheric reflector is not more than 10 orders. By adopting the concave even-order aspheric mirror with the aspheric coefficient not more than 10 orders, the field area and distortion of the image can be corrected.

In this embodiment, the imaging screen 2 is perpendicular to the base 1.

The working principle is as follows:

the light emitting element 31a (led) of the light source assembly 31 emits light beams, which are focused into nearly parallel light beams by the condenser lens 31b to reduce the entrance pupil diameter of the short-focus projection module; the parallel light beams enter the short-focus projection module and firstly pass through the display device 32, the display device 32 is in signal connection with the holographic projection control circuit, and the holographic projection control circuit generates image information with time on the display device 32; the parallel light beams are refracted by the refraction lens group 33 and then reflected to the imaging screen 2 through the aspheric surface reflector 34, and an enlarged imaging picture with time information is displayed on the imaging screen 2.

As an extension, the image on the imaging screen 2 may be pre-distorted to counteract the distortion of the short focus projection module, so that the image is clearer. The specific method of the pre-distortion treatment is as follows: a calibration model is established for each point in the image displayed by the display device 32, and the coordinates of the required undistorted image in the display device 32 after the transformation by the short-focus projection module are calculated to obtain a pre-distorted image. The image is applied in the display device 32 to be a distortion-free image after projection. The method can reduce the requirement on the short-focus projection module, thereby reducing the manufacturing cost.

Through testing, as shown in fig. 4, the cross part in the figure is the position to be imaged, and the part marked with the 'x' is the actual imaging position. From this figure, the maximum distortion is 3.8402%.

Second embodiment, as shown in fig. 5 to 6, the holographic projection clock in this embodiment is similar to the first embodiment, except that in this embodiment, the imaging screen 2 is obliquely fixed on the base 1 toward the short-focus projection module; in the refractive lens group 33, a double cemented lens is used as the first lens 33a, a double convex lens is used as the second lens 33b, and a negative crescent lens is used as the third lens 33 c. The spherical aberration, the coma aberration, the astigmatism and the chromatic aberration of the projection lens system can be better corrected by adopting the double cemented lens. Two lenses in the cemented lens should be matched by selecting materials with large abbe number (dispersive power) difference. The negative crescent lens can be made of PMMA material, so that the production cost is reduced.

Third embodiment, as shown in fig. 7, the holographic projection clock in this embodiment has a similar structure to that in the second embodiment, in the refractive lens group 33 of this embodiment, the first lens 33a is a biconvex lens, the second lens 33b is a doublet lens, and the third lens 33c is a negative crescent lens.

In the refractive lens group 33, a double cemented lens may be used for both the first lens 33a and the second lens 33 b.

The above is only a preferred embodiment of the present invention, and not intended to limit the scope of the invention, and it should be appreciated by those skilled in the art that various equivalent substitutions and obvious changes made in the specification and drawings should be included within the scope of the present invention.

Claims

1. A holographic projection clock comprises a base (1), and is characterized in that: base (1) on be fixed with imaging screen (2), base (1) still be provided with short burnt projection module and holographic projection control circuit, short burnt projection module including light source subassembly (31), display device (32), refraction battery of lens (33) and aspherical mirror (34) that arrange in proper order, refraction battery of lens (33) and aspherical mirror (34) constitute projection lens group, light source subassembly (31) including luminous piece (31a) and condensing lens (31b), holographic projection control circuit with display device (32) signal connection.

2. The holographic projection clock of claim 1, wherein: the projection lens group has a projection ratio of 0.35-0.4, a relative illumination greater than 80%, and a distortion rate less than 5%.

3. A holographic projection clock as claimed in claim 2, wherein: refracting lens group (33) including first lens (33a), second lens (33b) and third lens (33c) that the optical axis set up altogether in proper order, first lens (33a) be biconvex lens or two cemented lens, second lens (33b) be biconvex lens or two cemented lens, third lens (33c) be negative crescent moon lens.

4. A holographic projection clock as claimed in claim 3, wherein: and a diaphragm (33d) is arranged between the second lens (33b) and the third lens (33 c).

5. The holographic projection clock of claim 1, wherein: the display device (32) is an LCD display or a DMD display chip.

6. The holographic projection clock of claim 1, wherein: the aspheric surface reflector (34) adopts a concave even-order aspheric surface reflector, and the aspheric surface coefficient of the aspheric surface reflector is not more than 10 orders.

7. A holographic projection clock according to any of claims 1 to 6, characterized by: the imaging screen (2) is vertical to the base (1).

8. A holographic projection clock according to any of claims 1 to 6, characterized by: the imaging screen (2) is obliquely fixed on the base (1) towards the short-focus projection module.