An ultra-short-range large-view-field drawing projector optical system
By optimizing the component layout and materials of the optical system of the painting projector, ultra-short-distance large field-of-view projection is achieved, solving the problem of small field of view at large distances in existing technologies, and realizing efficient image projection and cost control.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- ZHONGSHAN MAVINLENS OPTICAL CO LTD
- Filing Date
- 2025-07-23
- Publication Date
- 2026-07-14
Smart Images
Figure CN224501128U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to an optical system for an ultra-short-distance, large-field-of-view painting projector. Background Technology
[0002] Currently, the optical systems of most painting projectors on the market have optical components spaced along a single optical axis. This requires a relatively large projection distance (generally exceeding 1 meter) and a small field of view (limiting image size), which is inconvenient for children because the long projection distance necessitates a larger space. The specific structure can be found in the utility model patent with patent number CN202023208682, entitled "A Projection Device Using an LCD Display." Therefore, there is a need to improve this product. Utility Model Content
[0003] The purpose of this invention is to provide an ultra-short-distance, large-field-of-view painting projector optical system, which solves the technical problem of existing painting projector optical systems having a large distance and a small field of view.
[0004] The technical solution of this utility model is implemented as follows:
[0005] An optical system for an ultra-short-throw, large-field-of-view drawing projector is characterized by comprising an objective lens, a reflector, a front Fresnel lens, an LCD display screen, a rear Fresnel lens, a reflector cup, and an LED light source. The reflector, front Fresnel lens, LCD display screen, rear Fresnel lens, reflector cup, and LED light source are sequentially distributed along the optical axis L1 at intervals. The objective lens is located below the reflector. The light emitted by the LED light source is collected by the reflector cup and reflected to the rear Fresnel lens. The rear Fresnel lens refracts the light into parallel rays, which are then uniformly projected onto the back of the LCD display screen. The image displayed on the front of the LCD display screen is focused by the front Fresnel lens and projected onto the reflector. After reflection by the reflector and magnification by the objective lens, a magnified real image is formed on the projection surface for children to copy and draw.
[0006] Preferably, the LED light source is an array-type LED light source.
[0007] Preferably, the objective lens includes objective lens one and objective lens two, which are structurally identical parts and are symmetrically mounted.
[0008] Preferably, both the front and rear Fresnel lenses are constructed with a flat surface on one side and a Fresnel surface with concentric circles of varying sizes engraved on the other side. Both the Fresnel surfaces of the front and rear Fresnel lenses face the LCD display screen.
[0009] Preferably, the materials of objective lens one and objective lens two are optical plastic materials with a refractive index in the range of 1.4n-1.6n and a dispersion coefficient in the range of 30μ-60μ.
[0010] Preferably, the front Fresnel lens, the reflector, objective lens one, and objective lens two together constitute a projection objective lens system, which projects the image displayed on the front of the LCD screen onto the projection surface.
[0011] Preferably, objective lens one, objective lens two, and the projection surface are distributed at intervals along the optical axis L2, and the optical axis L2 is perpendicular to the optical axis L1.
[0012] Preferably, the mirror, front Fresnel lens, LCD display, rear Fresnel lens, reflector cup, and LED light source are installed inside the housing. Objective lens one and objective lens two are installed inside a single objective lens tube. A spiral groove is provided at the exit cylinder at the bottom of the housing. The objective lens tube is fitted inside the exit cylinder, and the protrusions on the outer surface of the objective lens tube are nested in the spiral groove.
[0013] Preferably, focusing is achieved by adjusting the movement of the objective lens barrel along the optical axis L2.
[0014] Compared with the prior art, this utility model has the following advantages:
[0015] Effect 1: The optical system of this utility model painting projector can project an image of 190cm×142.5cm on a projection surface 220cm away from the objective lens, with a projection ratio of 1.158, and has the characteristics of ultra-short distance and large field of view.
[0016] Effect 2: Simple structure, reasonable layout, and low manufacturing cost.
[0017] Other advantages of this invention will be described in more detail in the Embodiments section. Attached Figure Description
[0018] Figure 1 This is a perspective view of the present utility model;
[0019] Figure 2 This is an exploded view of the present invention;
[0020] Figure 3 This is a cross-sectional view of the structure of this utility model;
[0021] Figure 4 This is a schematic diagram of the usage state of this utility model. Detailed Implementation
[0022] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.
[0023] Example 1:
[0024] like Figures 1 to 4 As shown, this embodiment provides an optical system for an ultra-short-throw, large-field-of-view drawing projector. Its features include: an objective lens 1, a reflector 2, a front Fresnel lens 3, an LCD display screen 4, a rear Fresnel lens 5, a reflector cup 6, and an LED light source 7. The reflector 2, front Fresnel lens 3, LCD display screen 4, rear Fresnel lens 5, reflector cup 6, and LED light source 7 are sequentially distributed along the optical axis L1 at intervals. The objective lens 1 is located below the reflector 2. The light emitted by the LED light source 7 is collected by the reflector cup 6 and reflected to the rear Fresnel lens 5. The rear Fresnel lens 5 refracts the light into parallel rays, which are then uniformly projected onto the back of the LCD display screen 4. The image displayed on the front of the LCD display screen 4 is focused by the front Fresnel lens 3 and projected onto the reflector 2. After reflection by the reflector 2 and magnification by the objective lens 1, a magnified real image is formed on the projection surface for children to copy and draw. It features an ultra-short distance and a large field of view, projecting an image of 190cm×142.5cm on a projection surface 220cm away from the objective lens, with a projection ratio of 1.158; it also has a simple structure, reasonable layout, and low manufacturing cost.
[0025] Preferably, the LED light source 7 is an array-type LED light source, which can be an array of LEDs arranged in 5 rows and 6 columns.
[0026] Preferably, the objective lens 1 includes objective lens one 11 and objective lens two 12. Objective lens one 11 and objective lens two 12 are structurally identical parts and are symmetrically installed, which effectively reduces the number of parts and lowers manufacturing and management costs.
[0027] Preferably, both the front Fresnel lens 3 and the rear Fresnel lens 5 are constructed with a flat surface on one side and a Fresnel surface with concentric circle textures of increasing size engraved on the other side. The Fresnel surfaces of the front Fresnel lens 3 and the rear Fresnel lens 5 face the LCD display screen 4, which is a reasonable layout.
[0028] Preferably, objective lens 11 and objective lens 2 12 are made of optical plastic material with a refractive index in the range of 1.4n-1.6n and a dispersion coefficient in the range of 30μ-60μ to ensure image clarity.
[0029] Preferably, the front Fresnel lens 3, the reflector 2, the first objective lens 11, and the second objective lens 12 together constitute a projection objective lens system, which projects the image displayed on the front of the LCD screen 4 onto the projection surface. The structure is simple and the layout is reasonable.
[0030] Preferably, objective lens 11, objective lens 2, and projection surface are distributed at intervals along optical axis L2, and optical axis L2 is perpendicular to optical axis L1.
[0031] Preferably, the reflector 2, the front Fresnel lens 3, the LCD display screen 4, the rear Fresnel lens 5, the reflector cup 6, and the LED light source 7 are installed inside the housing 10. Objective lens 11 and objective lens 2 12 are installed inside an objective lens tube 9. A spiral groove 81 is provided at the exit cylinder 8 at the bottom of the housing 10. The objective lens tube 9 is fitted inside the exit cylinder 8. The protrusions 91 on the outer surface of the objective lens tube 9 are nested in the spiral groove 81. The structure is simple.
[0032] Preferably, focusing is achieved by adjusting the movement of the objective lens tube 9 along the optical axis L2. Rotating the objective lens tube 9 causes the protrusion 91 on its outer surface to slide along the spiral groove 81, thereby adjusting the vertical movement of the objective lens tube 9 along the optical axis L2 for focusing.
[0033] Preferably, the housing 10 is assembled from an upper half-shell 10a and a lower half-shell 10b.
[0034] The above embodiments are preferred embodiments of the present utility model, but the embodiments of the present utility model are not limited thereto. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present utility model are equivalent substitutions and are included within the protection scope of the present utility model.
Claims
1. An optical system for an ultra-short-throw, large-field-of-view painting projector, characterized in that: It includes an objective lens (1), a reflector (2), a front Fresnel lens (3), an LCD display screen (4), a rear Fresnel lens (5), a reflector cup (6), and an LED light source (7). The reflector (2), the front Fresnel lens (3), the LCD display screen (4), the rear Fresnel lens (5), the reflector cup (6), and the LED light source (7) are arranged sequentially along the optical axis L1. The objective lens (1) is located below the reflector (2). The light emitted by the LED light source (7) is collected by the reflector cup (6) and reflected to the rear Fresnel lens (5). The rear Fresnel lens (5) refracts the light into parallel rays and projects them evenly onto the back of the LCD display screen (4). The image displayed on the front of the LCD display screen (4) is focused by the front Fresnel lens (3) and projected onto the reflector (2). After being reflected by the reflector (2) and magnified by the objective lens (1), a magnified real image is formed on the projection surface for children to copy and draw.
2. The optical system for an ultra-short-throw, large-field-of-view painting projector according to claim 1, characterized in that: The LED light source (7) adopts an array-type LED light source.
3. The optical system for an ultra-short-throw, large-field-of-view painting projector according to claim 1 or 2, characterized in that: The objective lens (1) includes objective lens one (11) and objective lens two (12). Objective lens one (11) and objective lens two (12) are parts with the same structure and are symmetrically installed.
4. The optical system for an ultra-short-throw, large-field-of-view painting projector according to claim 3, characterized in that: Both the front Fresnel lens (3) and the rear Fresnel lens (5) are constructed with a flat surface on one side and a Fresnel surface with concentric circles engraved on the other side. The Fresnel surfaces of the front Fresnel lens (3) and the rear Fresnel lens (5) face the LCD display screen (4).
5. The optical system for an ultra-short-throw, large-field-of-view painting projector according to claim 4, characterized in that: Objective lens 1 (11) and objective lens 2 (12) are made of optical plastic material with a refractive index in the range of 1.4n-1.6n and a dispersion coefficient in the range of 30μ-60μ.
6. The optical system for an ultra-short-throw, large-field-of-view painting projector according to claim 5, characterized in that: The front Fresnel lens (3), the mirror (2), the first objective lens (11) and the second objective lens (12) together constitute the projection objective lens system, which projects the image displayed on the front of the LCD screen (4) onto the projection surface.
7. The optical system for an ultra-short-throw, large-field-of-view painting projector according to claim 3, characterized in that: Objective lens 1 (11), objective lens 2 (12) and projection surface are distributed at intervals along optical axis L2, and optical axis L2 is perpendicular to optical axis L1.
8. The optical system for an ultra-short-throw, large-field-of-view painting projector according to claim 7, characterized in that: The mirror (2), front Fresnel lens (3), LCD display (4), rear Fresnel lens (5), reflector cup (6) and LED light source (7) are installed inside the housing (10). Objective lens one (11) and objective lens two (12) are installed inside an objective lens tube (9). A spiral groove (81) is provided at the exit cylinder (8) at the bottom of the housing (10). The objective lens tube (9) is fitted inside the exit cylinder (8). The protrusions (91) on the outer surface of the objective lens tube (9) are nested in the spiral groove (81).
9. The optical system for an ultra-short-throw, large-field-of-view painting projector according to claim 8, characterized in that: Focusing is achieved by adjusting the movement of the objective lens tube (9) along the optical axis L2.
10. The optical system for an ultra-short-throw, large-field-of-view painting projector according to claim 3, characterized in that: An image of 190cm×142.5cm can be projected onto the projection surface at a distance of 220cm from the objective lens, with a projection ratio of 1.158.