CN110109241B

CN110109241B - Telescope and focusing sheet

Info

Publication number: CN110109241B
Application number: CN201810101878.2A
Authority: CN
Inventors: 杨景州
Original assignee: Individual
Current assignee: Individual
Priority date: 2018-02-01
Filing date: 2018-02-01
Publication date: 2021-10-29
Anticipated expiration: 2038-02-01
Also published as: CN110109241A

Abstract

The invention discloses a telescope and a focusing sheet. The single-cylinder lens group comprises a lens barrel and a shading cylinder movably sleeved on the lens barrel, and the optical lens base is arranged in the shading cylinder and fixed on the lens barrel. The focusing sheet is transparent and arranged corresponding to the tail end part of the shading cylinder, and comprises a first surface and a second surface which are positioned on the opposite sides and are parallel to each other. The focusing sheet is provided with a plurality of focusing grooves which are linearly penetrated, the focusing grooves comprise a first groove, a second groove and a third groove, the length direction of the first groove and the length direction of the second groove jointly define an included angle smaller than 90 degrees, and the length direction of the third groove is parallel to an angular bisector of the included angle. The single-cylinder lens group and the optical lens base can be focused corresponding to the photographic object through the focusing groove. Therefore, the optical device adopting the focusing sheet can have better focusing effect through the configuration of the plurality of focusing grooves.

Description

Telescope and focusing sheet

Technical Field

The present disclosure relates to optical assemblies, and particularly to a telescope and a focusing lens.

Background

When using the existing telescope (such as a monocular telescope), a focusing lens is required to focus a photographic object. However, the conventional focusing sheet is mostly an opaque metal sheet, which limits the focusing effect of the optical device (e.g. telescope) using the conventional focusing sheet.

Therefore, the present inventors have found that the above-mentioned drawbacks can be improved, and have made intensive studies in cooperation with the application of scientific principles, and finally have proposed the present invention which is designed reasonably and effectively to improve the above-mentioned drawbacks.

Disclosure of Invention

The embodiment of the invention provides a telescope and a focusing sheet, which can effectively overcome the defects possibly generated by the conventional focusing sheet.

The embodiment of the invention discloses a telescope, which comprises: a monocular lens set comprising: a lens barrel; a shading cylinder movably sleeved on the lens cone; the optical lens base is arranged in the shading cylinder and fixed on the lens barrel, and comprises a tube body and a plurality of lenses which are positioned in the tube body and are arranged at intervals; a focusing sheet, which is transparent and is arranged corresponding to the tail end part of the shading cylinder, wherein the focusing sheet comprises a first surface and a second surface which are positioned on opposite sides and are parallel to each other, and the first surface faces the optical lens seat; the focusing sheet is provided with a plurality of focusing grooves which are linearly penetrated, the plurality of focusing grooves comprise at least one first groove, at least one second groove and at least one third groove, the length direction of at least one first groove and the length direction of at least one second groove jointly define an included angle smaller than 90 degrees, and the length direction of at least one third groove is parallel to an angle bisector of the included angle; the single-cylinder lens group and the optical lens base can be focused corresponding to a photographic object through the focusing grooves of the focusing film.

Preferably, the telescope further comprises a bracket detachably mounted on the end portion, the focusing sheet comprises a focusing area in a circular shape and a mounting area located outside the focusing area, and the focusing sheet is configured on the bracket through the mounting area and is arranged corresponding to the end portion; the focusing sheet is provided with a plurality of focusing grains on the first surface, the focusing area is defined with four quadrants, the focusing grains are respectively positioned in the four quadrants, and the focusing grooves are respectively positioned in the four quadrants.

Preferably, the four quadrants are further defined as a first quadrant, a second quadrant, a third quadrant, and a fourth quadrant of equal area; the plurality of focusing grains comprise: a plurality of first textures located in parallel with each other in the first quadrant; wherein one of the first lines is connected with the center of the focus area; a plurality of second textures located in parallel in the second quadrant; wherein one of the second lines is connected to the center of the focus area; a plurality of third textures located in parallel in the third quadrant and the fourth quadrant; wherein one of the third lines is connected to the center of the focus area, and the first line, the second line and the third line connected to the center of the focus area form a Y-shaped line together; wherein the plurality of focusing grooves include a plurality of first grooves formed in the first quadrant, a plurality of second grooves formed in the second quadrant, and a plurality of third grooves formed in the third quadrant and the fourth quadrant; a plurality of said first grooves are parallel to each of said first ridges, a plurality of said second grooves are parallel to each of said second ridges, and a plurality of said third grooves are parallel to each of said third ridges.

Preferably, each third texture except the Y-shaped texture is connected to one first texture or one second texture and forms an obtuse angle, and a plurality of first textures which are not connected to the third texture are respectively connected to a plurality of second textures which are not connected to the third texture, and each connected first texture forms an acute angle with the corresponding second texture; wherein one of the first grooves and one of the second grooves adjacent to each other are connected to form a V-shaped groove together, and the plurality of focusing grooves other than the V-shaped groove are disposed apart from each other.

Preferably, the focusing region is defined with: a circular fringe area, the center of which is overlapped with the center of the focus area, and the ratio of the radius of the focus area to the radius of the circular fringe area is approximately between 3 and 5; wherein the circular stripe region is provided with a plurality of portions of the focusing lines, and the circular stripe region is not formed with any focusing grooves; the annular mixing area surrounds the circular stripe area, and is provided with a plurality of focusing grooves and the rest parts of the focusing grains; wherein an outer end edge of each of the focusing grooves falls on an outer boundary of the annular mixing zone, and an inner end edge of a part of the focusing grooves among the plurality of focusing grooves falls on an inner boundary of the annular mixing zone.

The embodiment of the invention also discloses a focusing sheet which is transparent and comprises: a first surface and a second surface located on opposite sides and parallel to each other; the focusing sheet is provided with a plurality of focusing grains on the first surface, and a plurality of penetrating focusing grooves; the focusing lines and the focusing grooves of the focusing sheet can be used for providing an optical device for focusing corresponding to a photographic object.

Preferably, the focusing plate comprises a focusing area in a circular shape and a mounting area located outside the focusing area; the focusing region is defined with: a circular fringe area, the center of which is overlapped with the center of the focus area, and the ratio of the radius of the focus area to the radius of the circular fringe area is approximately between 3 and 5; wherein the circular stripe region is provided with a plurality of portions of the focusing lines, and the circular stripe region is not formed with any focusing grooves; and the annular mixing area surrounds the circular stripe area, and is provided with a plurality of focusing grooves and the rest parts of the focusing grains.

Preferably, the focusing lens defines a first quadrant, a second quadrant, a third quadrant and a fourth quadrant with equal area; the focusing grains comprise a plurality of first grains which are parallel to each other and positioned in the first quadrant, a plurality of second grains which are parallel to each other and positioned in the first quadrant, and a plurality of third grains which are parallel to each other and positioned in the third quadrant and the fourth quadrant; wherein the focusing grooves comprise a plurality of first grooves formed in the first quadrant, a plurality of second grooves formed in the second quadrant, and a plurality of third grooves formed in the third quadrant and the fourth quadrant; a plurality of said first grooves are parallel to each of said first ridges, a plurality of said second grooves are parallel to each of said second ridges, and a plurality of said third grooves are parallel to each of said third ridges.

Preferably, one of the first textures is connected to the center of the focus area, one of the second textures is connected to the center of the focus area, and one of the third textures is connected to the center of the focus area; the first lines, the second lines and the third lines connected to the circle center form Y-shaped lines together; each third grain except the Y-shaped grain is connected with one first grain or one second grain and forms an obtuse angle, a plurality of first grains which are not connected with the third grain are respectively connected with a plurality of second grains which are not connected with the third grain, and each connected first grain and the corresponding second grain form an acute angle: wherein one of the first grooves and one of the second grooves adjacent to each other are connected to form a V-shaped groove together, and the plurality of focusing grooves other than the V-shaped groove are disposed apart from each other; the focusing groove is formed in the substrate, the focusing groove is formed between any two adjacent and parallel focusing lines, a space is formed between any two adjacent and parallel focusing lines, each focusing groove is provided with a groove width, and the groove width is approximately 2-8 times of the space.

The embodiment of the invention also discloses a focusing sheet, which is transparent and comprises: a first surface and a second surface located on opposite sides and parallel to each other; the focusing sheet is provided with a plurality of focusing grooves which are linearly penetrated, the plurality of focusing grooves comprise at least one first groove, at least one second groove and at least one third groove, an included angle which is smaller than 90 degrees is defined by the length direction of the at least one first groove and the length direction of the at least one second groove, and the length direction of the at least one third groove is parallel to an angle bisector of the included angle. In summary, the telescope disclosed in the embodiments of the present invention uses the transparent focusing sheet and the direction arrangement between the plurality of focusing grooves (or the matching of the plurality of focusing lines and the plurality of focusing grooves) to make the optical device (e.g., the telescope) using the focusing sheet have a better focusing effect.

For a better understanding of the nature and technical content of the present invention, reference should be made to the following detailed description of the invention, taken in conjunction with the accompanying drawings, which are provided for purposes of illustration and description and are not intended to limit the scope of the invention in any way.

Drawings

FIG. 1 is a perspective view of a telescope according to the present invention.

Fig. 2 is a schematic cross-sectional view of fig. 1 along the sectional line ii-ii.

Fig. 3 is a partially exploded view of fig. 1.

FIG. 4 is a schematic plan view of a focusing sheet according to the present invention.

FIG. 5 is a schematic plan view of a focusing sheet according to the present invention.

FIG. 6 is a schematic plan view of another type of focusing sheet of the present invention.

Detailed Description

Referring to fig. 1 to 5, it should be noted that, in the embodiment of the present invention, relevant numbers and shapes mentioned in the corresponding drawings are only used for describing the embodiments of the present invention in detail, so as to facilitate understanding of the content of the present invention, and are not used for limiting the scope of the present invention.

As shown in fig. 1 to 3, the present embodiment discloses a telescope 100, particularly a monocular telescope or an astronomical telescope, but the present invention is not limited thereto. The telescope 100 includes a single cylinder type lens barrel set 1, an optical lens holder 2 fixed in the single cylinder type lens barrel set 1, and a focusing lens 3 disposed corresponding to the single cylinder type lens barrel set 1. Further, the telescope 100 of the present embodiment includes a bracket 4 detachably mounted on the monocular lens set 1 for correspondingly disposing the focusing lens 3 on the monocular lens set 1, but the present invention is not limited thereto. That is, in other embodiments not shown in the present disclosure, the focusing lens 3 may also be directly mounted on a related component of an optical device.

It should be noted that although the focusing sheet 3 of the present embodiment is described as being associated with the single cylinder type lens set 1, in other embodiments not shown in the present invention, the focusing sheet 3 may be sold separately or applied to other optical devices, and is not limited to the embodiment.

As shown in fig. 1 to 3, the single-cylinder lens set 1 includes a lens barrel 11 and a light-shielding cylinder 12 movably sleeved on the lens barrel 11, the lens barrel 11 includes at least one lens (not shown), and the light-shielding cylinder 12 is a hollow tube and has no lens fixed on its inner edge. The optical lens base 2 is disposed in the light-shielding cylinder 12 and fixed on the lens barrel 11, and the optical lens base 2 includes a tube 21 fixed on the lens barrel 11 and a plurality of lenses 22 disposed in the tube 21 and spaced from each other. Furthermore, the light shielding cylinder 12 can move along the long axis direction of the lens barrel 11 to extend the light entrance path of the optical lens holder 2, and further block the external light from interfering with the plurality of lenses 22 in the optical lens holder 2.

The bracket 4 is detachably mounted on the end portion 121 of the light shielding cylinder 12, and the assembly manner between the bracket 4 and the light shielding cylinder 12 can be adjusted according to the requirement of the designer, which is not limited herein. In the present embodiment, the end portion 121 of the light shielding cylinder 12 is directly inserted into the bracket 4, so as to abut against the end portion 121 of the light shielding cylinder 12 through the inner edge of the bracket 4.

As shown in fig. 3, the focusing sheet 3 is transparent and disposed corresponding to the end portion 121 of the light shielding cylinder 12, that is, the focusing sheet 3 may be made of a transparent material such as glass or acryl. The focusing sheet 3 includes a first surface 3a and a second surface 3b that are opposite and parallel to each other, and the first surface 3a and the second surface 3b are planar in this embodiment, and the first surface 3a of the focusing sheet 3 faces the optical lens holder 2.

Furthermore, the focusing sheet 3 includes a focusing area 31 and a mounting area 32 located outside the focusing area 31, and the mounting area 32 is detachably located on the bracket 4, so that the focusing sheet 3 can be disposed corresponding to the end portion 121 of the shading cylinder 12 by disposing the mounting area 32 on the bracket 4. However, the structure of the bracket 4 or the positioning manner between the focusing sheet 3 and the bracket 4 may be adjusted or changed according to the needs of the designer, and the invention is not limited thereto.

In the present embodiment, the frame 4 includes a plurality of positioning structures (not shown), the mounting region 32 is formed with a plurality of engaging structures 321, and the focusing lens 3 is assembled to the plurality of positioning structures through the plurality of engaging structures 321 to maintain a relative position with the frame 4. In more detail, each positioning structure can be a screw, and each matching structure 321 is a through hole formed in the mounting area 32. The focusing sheet 3 is fixed to the bracket 4 by the positioning structures (e.g., screws) passing through the matching structures 321 (e.g., holes) of the mounting region 32, so as to maintain the relative position of the focusing sheet 3 and the light-shielding cylinder 12.

Furthermore, the mounting region 32 is annular and surrounds the outer side of the focusing region 31 in this embodiment, but the invention is not limited thereto. For example: in an embodiment not shown in the present invention, the mounting area 32 may also include a plurality of annularly arranged sheet bodies, and the positioning structures (e.g., screws) may be respectively fixed to the plurality of sheet bodies of the mounting area 32.

In addition, in another embodiment not shown in the present invention, the bracket 4 may also be a plurality of cylinders movably disposed through the mounting area 32, and the focusing lens 3 can be clamped and positioned on the end portion 121 of the shading cylinder 12 by the plurality of cylinders.

The focusing sheet 3 is formed with a plurality of focusing lines 311 on the first surface 3a thereof, and the focusing sheet 3 is formed with a plurality of focusing grooves 312 in a straight-line penetrating manner; the single-cylinder lens barrel set 1 and the optical lens base 2 can focus corresponding to a photographic object (such as a star point) through the focusing lines 311 and the focusing grooves 312 of the focusing sheet 3. The size of the focusing sheet 3 and the specific shape of the focusing area 31 and the focusing groove 312 can be adjusted according to the needs of the designer, and the invention is not limited thereto.

In the present embodiment, as shown in fig. 3 and 4, the focusing area 31 of the focusing sheet 3 is circular and can define four quadrants Q1-Q4. The focusing grooves 311 are respectively located in the four quadrants Q1-Q4, and the focusing grooves 312 are also respectively located in the four quadrants Q1-Q4.

More specifically, the four quadrants Q1-Q4 of the focusing region 31 are further defined as a first quadrant Q1, a second quadrant Q2, a third quadrant Q3, and a fourth quadrant Q4 of equal area. The focusing lines 311 include a plurality of first lines 3111 located in the first quadrant Q1, a plurality of second lines 3112 located in the second quadrant Q2, and a plurality of third lines 3113 located in the third quadrant Q3 and the fourth quadrant Q4.

The first lines 3111 are parallel to each other and have different lengths, and one of the first lines 3111' of the first lines 3111 is connected to a center C of the focus area 31. The second ridges 3112 are parallel to each other and have different lengths, and one of the second ridges 3112' of the second ridges 3112 is connected to a center of the focus area 31. The third grooves 3113 are parallel to each other and have different lengths, and one third groove 3113' of the third grooves 3113 is connected to a center C of the focus area 31.

Furthermore, the first vein 3111 ', the second vein 3112 ', and the third vein 3113 ' connected to the center C of the focusing area 31 together form a Y-shaped vein. That is, the lengths of the first groove 3111 ', the second groove 3112 ' and the third groove 3113 ' are substantially equal to the radius of the focusing area 31 of the focusing sheet 3, but the invention is not limited thereto. In addition, the first vein 3111 'and the second vein 3112' form an acute angle, and the first vein 3111 'and the third vein 3113' form an obtuse angle, and the angle is equal to the acute angle formed by the second vein 3112 'and the third vein 3113'.

Also, each third vein 3113 other than the Y-shaped vein is connected to one first vein 3111 or one second vein 3112 and forms an obtuse angle therebetween, and a plurality of first veins 3111 not connected to the third vein 3113 are respectively connected to a plurality of second veins 3112 not connected to the third vein 3113, and each connected first vein 3111 forms an acute angle with the corresponding second vein 3112.

The focusing grooves 312 include a plurality of first grooves 3121 formed in the first quadrant Q1, a plurality of second grooves 3122 formed in the second quadrant Q2, and a plurality of third grooves 3123 formed in the third quadrant Q3 and the fourth quadrant Q4. Wherein the plurality of first grooves 3121 are parallel to each of the first grooves 3111, the plurality of second grooves 3122 are parallel to each of the second grooves 3112, and the plurality of third grooves 3123 are parallel to each of the third grooves 3113.

More specifically, the first grooves 3121 and the first ridges 3111 are alternately arranged, the second grooves 3122 and the second ridges 3112 are alternately arranged, and the third grooves 3123 and the third ridges 3113 are alternately arranged. At least three focusing grooves 311 are preferably disposed between any two adjacent and parallel focusing grooves 312 (e.g., at least three first grooves 3111 are disposed between two adjacent first grooves 3121), but the invention is not limited thereto.

Furthermore, any two adjacent and parallel focusing lines 311 are separated by a distance D, and each focusing groove 312 has a groove width W, which is approximately 2 to 8 times the distance. In the embodiment, the groove width W is approximately 4 to 5 times the distance D, but the invention is not limited thereto. Furthermore, the length of each focusing groove 312 is preferably smaller than the radius of the focusing area 31.

In this embodiment, one of the first grooves 3121 'and one of the second grooves 3122' adjacent to each other are connected to form a V-shaped groove, the V-shaped groove is located between the first groove 3111 'and the second groove 3112' of the Y-shaped groove, and the plurality of focusing grooves 312 outside the V-shaped groove are separately disposed from each other, but the invention is not limited thereto.

However, the number of the first groove 3121, the second groove 3122, and the third groove 3123 is not limited to a plurality, that is, the focusing grooves 312 may include at least one first groove 3121, at least one second groove 3122, and at least one third groove 3123. An included angle smaller than 90 degrees is defined by the length direction of the at least one first groove 3121 and the length direction of the at least one second groove 3122, and the length direction of the at least one third groove 3123 is parallel to an angular bisector of the included angle. In this embodiment, the extension line of the angle bisector of the included angle is overlapped with the third striations 3113', and the angle of the included angle is preferably smaller than 60 degrees (e.g., 30 degrees to 45 degrees), but the invention is not limited thereto.

In another view, as shown in fig. 4 and 5, the focusing region 31 can also be defined as a circular stripe region 31a and an annular mixing region 31b surrounding the circular stripe region 31 a. The center of the circular stripe region 31a overlaps the center C of the focus region 31, and the radius of the focus region 31 is preferably a ratio of 3 to 5 with respect to the radius of the circular stripe region 31a, but the invention is not limited thereto.

Further, the circular stripe region 31a is provided with the portions of the plurality of focusing ridges 311, and the circular stripe region 31a is not formed with any focusing grooves 312. Furthermore, the annular mixing region 31b is provided with the rest of the focusing lines 311 and the focusing grooves 312. Wherein an outer end edge of each of the focusing grooves 312 falls on an outer boundary of the annular mixing zone 31b, and an inner end edge of a part of the focusing grooves 312 among the plurality of focusing grooves 312 falls on an inner boundary of the annular mixing zone 31 b.

In addition, in other embodiments not shown in the present invention, the focusing sheet 3 may also have a circular hole formed in the circular stripe region 31a, and each focusing groove 312 is not connected to the circular hole. Furthermore, the focusing sheet 3 may also be formed with only the focusing grooves 312 (i.e. the focusing sheet 3 is not formed with any focusing lines 311) as shown in fig. 6, so that the optical device (e.g. the telescope 100) using the focusing sheet 3 can have a better focusing effect by the directional arrangement between the focusing grooves 312.

It should be noted that, when the telescope 100 of the present embodiment completes focusing through the focusing sheet 3, the photographic object (e.g., a star point) presents a specific pattern (e.g., the star point presents three clear and interlaced lines), so as to facilitate the user to determine whether the focusing is completed.

[ technical effects of the embodiments of the present invention ]

In summary, the telescope disclosed in the embodiments of the present invention uses the transparent focusing sheet and the direction arrangement between the plurality of focusing grooves (or the matching of the plurality of focusing lines and the plurality of focusing grooves) to make the optical device (e.g., the telescope) using the focusing sheet have a better focusing effect.

Furthermore, the focusing sheet of the present embodiment can further improve the focusing effect of the optical device using the focusing sheet by the further matching design of the plurality of focusing lines and the plurality of focusing grooves (e.g., the circular stripe region and the annular mixed region, the focusing lines and the focusing grooves in the same quadrant are parallel to each other, the Y-shaped stripe and the V-shaped groove, the distance between any two adjacent focusing lines with the focusing groove width approximately 2-8 times, and at least three focusing lines arranged between any two adjacent and parallel focusing grooves).

The above description is only a preferred embodiment of the present invention, and should not be taken as limiting the scope of the invention, which is defined by the appended claims.

Claims

1. A telescope, the telescope comprising:

a monocular lens set comprising:

a lens barrel; and

a shading cylinder movably sleeved on the lens cone;

the optical lens base is arranged in the shading cylinder and fixed on the lens barrel, and comprises a tube body and a plurality of lenses which are positioned in the tube body and are arranged at intervals; and

a focusing sheet, which is transparent and is arranged corresponding to the tail end part of the shading cylinder, wherein the focusing sheet comprises a first surface and a second surface which are positioned on opposite sides and are parallel to each other, and the first surface faces the optical lens seat; the focusing sheet is provided with a plurality of focusing grains on the first surface, the focusing sheet is provided with a plurality of focusing grooves which are linearly penetrated, a space is formed between any two adjacent and parallel focusing grains, each focusing groove is provided with a groove width which is 2-8 times of the space, the focusing grooves comprise at least one first groove, at least one second groove and at least one third groove, the length direction of at least one first groove and the length direction of at least one second groove jointly define an included angle which is less than 90 degrees, and the length direction of at least one third groove is parallel to an angular bisector of the included angle;

the single-cylinder lens group and the optical lens base can focus corresponding to a photographic object through a plurality of focusing lines and a plurality of focusing grooves of the focusing sheet;

the focusing sheet comprises a circular focusing area and a mounting area positioned outside the focusing area, the focusing area is defined with four quadrants, a plurality of focusing grains are respectively positioned in the four quadrants, and the four quadrants are further defined as a first quadrant, a second quadrant, a third quadrant and a fourth quadrant with equal areas; the plurality of focusing grains comprise:

a plurality of first textures located in parallel with each other in the first quadrant; wherein one of the first lines is connected with the center of the focus area;

a plurality of second textures located in parallel in the second quadrant; wherein one of the second lines is connected to the center of the focus area; and

a plurality of third textures located in parallel in the third quadrant and the fourth quadrant; wherein one of the third lines is connected to the center of the focus area, and the first line, the second line and the third line connected to the center of the focus area form a Y-shaped line together.

2. The telescope according to claim 1, further comprising a mount detachably mounted to the distal end portion, the focusing plate being disposed in the mount through the mounting portion and corresponding to the distal end portion; and the focusing grooves are also respectively positioned in the four quadrants.

3. The telescope according to claim 2, wherein the plurality of focusing grooves comprises a plurality of first grooves formed in the first quadrant, a plurality of second grooves formed in the second quadrant, and a plurality of third grooves formed in the third quadrant and the fourth quadrant; a plurality of said first grooves are parallel to each of said first ridges, a plurality of said second grooves are parallel to each of said second ridges, and a plurality of said third grooves are parallel to each of said third ridges.

4. The telescope according to claim 3, wherein each of the third lines other than the Y-shaped lines is connected to one of the first lines or one of the second lines and forms an obtuse angle with each other, and a plurality of the first lines not connected to the third lines are respectively connected to a plurality of the second lines not connected to the third lines, and each of the connected first lines forms an acute angle with the corresponding second line; wherein one of the first grooves and one of the second grooves adjacent to each other are connected to form a V-shaped groove together, and the plurality of focusing grooves other than the V-shaped groove are disposed apart from each other.

5. The telescope according to any one of claims 2 to 4, wherein the focusing region defines:

a circular fringe area, the center of which is overlapped with the center of the focus area, and the ratio of the radius of the focus area to the radius of the circular fringe area is between 3 and 5; wherein the circular stripe region is provided with a plurality of portions of the focusing lines, and the circular stripe region is not formed with any focusing grooves; and

the annular mixing area surrounds the circular stripe area, and is provided with a plurality of focusing grooves and the rest parts of the focusing grains; wherein an outer end edge of each of the focusing grooves falls on an outer boundary of the annular mixing zone, and an inner end edge of a part of the focusing grooves among the plurality of focusing grooves falls on an inner boundary of the annular mixing zone.

6. A focusing sheet, characterized in that the focusing sheet is transparent and comprises: a first surface and a second surface located on opposite sides and parallel to each other; the focusing sheet is provided with a plurality of focusing grains on the first surface, a plurality of penetrating focusing grooves are formed in the focusing sheet, a space is formed between any two adjacent and parallel focusing grains, each focusing groove is provided with a groove width, and the groove width is 2-8 times of the space; the focusing lines and the focusing grooves of the focusing sheet can be used for providing an optical device for focusing corresponding to a photographic object;

the focusing sheet comprises a circular focusing area and a mounting area positioned outside the focusing area, and the focusing area of the focusing sheet defines a first quadrant, a second quadrant, a third quadrant and a fourth quadrant with equal areas; the focusing grains comprise a plurality of first grains which are parallel to each other and positioned in the first quadrant, a plurality of second grains which are parallel to each other and positioned in the first quadrant, and a plurality of third grains which are parallel to each other and positioned in the third quadrant and the fourth quadrant; wherein one of the first plurality of lines is connected to the center of the focal region, one of the second plurality of lines is connected to the center of the focal region, and one of the third plurality of lines is connected to the center of the focal region; the first lines, the second lines and the third lines connected to the circle center form Y-shaped lines together.

7. The focusing sheet of claim 6, wherein the focusing region is defined with:

and the annular mixing area surrounds the circular stripe area, and is provided with a plurality of focusing grooves and the rest parts of the focusing grains.

8. The focusing plate as claimed in claim 6, wherein the focusing grooves include a plurality of first grooves formed in the first quadrant, a plurality of second grooves formed in the second quadrant, and a plurality of third grooves formed in the third quadrant and the fourth quadrant; a plurality of said first grooves are parallel to each of said first ridges, a plurality of said second grooves are parallel to each of said second ridges, and a plurality of said third grooves are parallel to each of said third ridges.

9. The focusing sheet according to claim 8, wherein each of the third ridges other than the Y-shaped ridges is connected to one of the first ridges or one of the second ridges and forms an obtuse angle with each other, and a plurality of the first ridges not connected to the third ridges are respectively connected to a plurality of the second ridges not connected to the third ridges, and each of the connected first ridges forms an acute angle with the corresponding second ridge: wherein one of the first grooves and one of the second grooves adjacent to each other are connected to form a V-shaped groove together, and the plurality of focusing grooves other than the V-shaped groove are disposed apart from each other.

10. A focusing sheet, characterized in that the focusing sheet is transparent and comprises: a first surface and a second surface located on opposite sides and parallel to each other; the focusing sheet is provided with a plurality of focusing grains on the first surface, the focusing sheet is provided with a plurality of focusing grooves which are linearly penetrated, any two adjacent and parallel focusing grains are separated by a space, each focusing groove is provided with a groove width which is 2-8 times of the space, the focusing grooves comprise at least one first groove, at least one second groove and at least one third groove, the length direction of at least one first groove and the length direction of at least one second groove jointly define an included angle smaller than 90 degrees, and the length direction of at least one third groove is parallel to an angular bisector of the included angle;