Concentration Support Device
The headband with a central cutout and protrusions provides a cost-effective solution for auditory and visual isolation, enhancing concentration by creating a tunnel effect, allowing users to concentrate on personal activities and reflexively maintain focus without the device.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2024-03-19
- Publication Date
- 2026-04-10
AI Technical Summary
Existing concentration-enhancing devices are complex, costly, and fail to provide both auditory and visual isolation necessary for effective concentration, often requiring users to engage in specific activities dictated by the device and not understood by others around them.
A simple, inexpensive headband with a central cutout and protrusions that restrict lateral vision and cover the ears, allowing a forward field of view while isolating the user from auditory and visual distractions, optionally featuring adjustable fastening and ear pads for enhanced noise reduction.
Facilitates concentration by creating a visual and auditory tunnel effect, enabling users to concentrate on personal activities independently and reflexively, with others understanding the need for isolation.
Smart Images

Figure 2026510961000001_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a device for assisting concentration and isolation, and is targeted at people who, regardless of age group (children, young people or adults), especially when there is noise or commotion around them in a confined space, cannot concentrate when performing personal activities, or simply want to be alone.
[0002] Often, simply telling a person (especially a child, etc.) to "concentrate" does not resonate with the person, so there is a need to obtain a tool that can assist in concentration, especially when a person should be concentrating on an activity in the learning stage.
Background Art
[0003] Currently, there are the following four types of devices for assisting a person to concentrate on an activity:
[0004] A soundproof headset-type instrument as taught in the patent application KR20150028792A in 2015. This instrument, on the one hand, does not cause annoyance to surrounding people because the sound generated inside the instrument does not leak outside, and on the other hand, blocks external noise and provides an environment where one can concentrate without being troubled by external noise, thereby enhancing concentration.
[0005] Glasses or a headband provided with side shields that narrow the left and right viewing angles, as taught in the patent application JP-A-0990285, or a headband in the shape of a headset with semi-circular side shields that narrow the left and right viewing angles to concentrate a student's attention forward and also prevent cheating during a test, as taught in the application JP-A-0990865.
[0006] Concentration education support based on a game or a complex special device that arouses and attracts the attention of people and / or children, as described in the utility model registration applications CN215895737 or CN208954409.
[0007] Finally, there's a detachable concentration screen consisting of three panels (which are foldable). It can be placed on a table or desk to create a temporarily quiet U-shaped workspace, minimizing distractions from auditory and visual stimuli. The space created between the two side panels that form the vertical line of the U allows students or others to place their heads inside, making it easier to concentrate.
[0008] While these known devices certainly allow people to concentrate on personal activities in their own unique ways, they are complex and therefore costly. Alternatively, while they may enhance concentration, the user may be unable to engage in activities other than those suggested by the device itself. Or, they fail to meet the two criteria necessary for good concentration: silence and visual deprivation—the criteria for preventing the person seeking concentration from being distracted by surrounding noise.
[0009] Prior art is also described by the teachings in document WO2011 / 137463. This document discloses a traveler's rest eye mask that includes means for completely covering the traveler's eyes to block out light and reduce sound. Its purpose is to facilitate rest and sleep by blocking out sight and hearing. Thus, this eye mask is not intended for performing any activity. [Overview of the project]
[0010] The challenge, therefore, is to create a simple (i.e., inexpensive) universal device that helps people concentrate on personal activities, especially when they need to be isolated from their environment both auditorily and visually, such as when learning or performing specific tasks independent of the device itself (like children reading and writing). This device also aims to address the problem that the need for peace and quiet for concentration is often not understood by those around the person.
[0011] A solution to these challenges is a concentration support device that assists the concentration of any person, the concentration support device including a headband capable of encircling the person's forehead and head, the headband having an inner surface intended to face the person's forehead and temples, and an outer surface facing it, - A central cutout intended to be positioned in front of a person's eyes, - Two protrusions surrounding both sides of the notch, which are intended to be placed over a person's ear and cover the ear. Equipped with, The concentration support device includes a contact band located on the inner surface of the headband, at least above the central cutout, which can move the headband away from the person's forehead. As a result, the contact band, together with the central cutout, allows for a forward field of view, which is laterally restricted by two protrusions that form two eye-blocking strips that can limit the lateral field of view.
[0012] When worn, the central notch in the headband comes into contact with the eyes (i.e., directly in front of the eyes), while the contact band separates the headband from the forehead. The combined effect of these elements widens the field of vision. In fact, the contact band creates space between the headband and the eyes, and the central notch allows for a field of vision to be opened within this space. It is self-evident that the field of vision is secured within the headband while the central notch constrains the field of vision within limits based on its shape and size.
[0013] Furthermore, it is self-evident that the central notch defines a recessed area (i.e., an empty space) within the headband, and when it is stated that the central notch is positioned in front of the eyes, it means that the recessed area (i.e., empty space) is positioned in front of the eyes. In other words, if the recessed area is defined by the top edge, this top edge is located above the line of sight axis, and a person's eyes are aligned along this axis connecting the two eyes. This central notch is also defined by the (left and right) side edges, which extend below this line of sight axis, forming the edges of protrusions on both sides of the central notch.
[0014] Furthermore, the protrusions restrict this field of view, and more generally, it is the edges (or sides) of the central notch that restrict this field of view laterally (to the right or left) and upward. By ensuring a field of view within the limits provided by the central notch, a person can work (for example, reading, writing, drawing) in a state of isolation, so to speak, within a visual tunnel.
[0015] Furthermore, the present invention solves all the problems by providing a simple and inexpensive device for anyone who wishes to concentrate on personal activities. The device helps to isolate the person from their auditory environment by ear-covering protrusions and, optionally, pads, particularly when learning or practicing a specific task independent of the device itself, and from their visual environment by side protrusions that form an eye patch that restricts their field of vision so that they can only see what is directly in front of them.
[0016] Thus, the present invention proposes that for people who want to concentrate on personal activities, they should wear a device based on the present invention while performing these activities that require concentration, and "retreat into their own world."
[0017] Furthermore, this invention makes it possible to effectively acquire concentration. This is because, after the learning phase using this type of device, one will be able to concentrate automatically even without the device. In fact, without this tool, a person would reflexively put their hand to their temple to narrow their field of vision.
[0018] In one preferred embodiment, the headband according to the present invention is - On the other hand, a component made of a long, narrow flexible sheet, having a relatively narrow central portion that forms a notch, and having relatively wide sides that form protrusions capable of covering a person's ears, - On the other hand, a fixing system that can connect both ends of the part to keep the part around a person's head, It consists of.
[0019] This type of embodiment is extremely advantageous because it is based on a thin and flexible sheet that can be easily manufactured at low cost.
[0020] According to another feature of the present invention, in order to make other people understand that the person wearing the device needs isolation, the headband has at least one word expressing silence, such as "chut (quietly)", on its outer surface. Thus, other people who notice that this person wants to concentrate are thought to become quiet, which meets one of the purposes of the present invention.
[0021] According to one feature, the flexible sheet is made of a plastic material.
[0022] According to another feature, the fixing system that connects both ends of the component can adjust the length according to the person's head. [[ID=According to one possibility, the abutment band is at least partially made of a foam material. Thus, the foam abutment band that contacts the forehead is flexible and improves comfort.
[0029] According to another possibility, the headband has a lower edge provided with a central notch and an upper edge opposite the lower edge along which the abutment band is arranged.
[0030] According to another possibility, the central notch is defined by an upper side and two side sides each contacting two protrusions.
[0031] In an advantageous embodiment, the length of the upper side is 8 to 12 centimeters. Such a length can cover both eyes that are separated.
[0032] This length of the upper side is measured along the longitudinal direction parallel to the line of sight axis. This line of sight axis is an axis passing through the centers of both eyes of a person. The upper side can be straight or curved.
[0033] According to one feature, the lengths of the two side sides are each 5 to 10 centimeters.
[0034] By making the side sides this length, the protrusions extend far enough below the line of sight axis, thereby enhancing the required tunnel effect.
[0035] According to one feature, the central notch is defined by a line of curved or bent sides that are generally inverted "U" - shaped as a whole.
[0036] According to another feature, the width of each protrusion is 10 to 20 centimeters, for example 13 to 18 centimeters.
[0037] Such a width measured in the vertical direction when a person is wearing it extends to the sides of the cheeks below the cheekbones on both sides of the central notch, enhancing the isolation effect.
[0038] The present invention relates to the use of the concentration support device according to the present invention, which assists a person in concentrating, wherein the central cutout is positioned in front of the person's eyes, and the contact band is positioned facing the person's forehead to keep the headband away from the person's forehead and secure a forward field of view, so that the headband surrounds the person's forehead and head, and this field of view is laterally restricted by the two protrusions.
[0039] In one advantageous use, the central notch is defined by the top edge, the person's eyes are aligned along the line of sight axis, and the headband is positioned on the person's head such that the top edge is located above the line of sight axis.
[0040] Advantageously, the top edge is located at a predetermined distance above the line of sight axis, and this distance is a maximum of 3 centimeters, for example, 1 to 2 centimeters.
[0041] This distance allows for a constrained field of vision, resulting in the desired tunneling effect. In fact, when a person looks down to concentrate on an activity at a table (such as reading, writing, coloring, or drawing), the top edge obstructs the view above, thereby enhancing the desired tunneling effect.
[0042] Other features and advantages of the present invention will become clear as you read the following detailed description with reference to the accompanying drawings, which are intended to aid in understanding. Note that the drawings do not limit the scope of the present invention, and other embodiments are possible.
[0043] For the purpose of describing and understanding the present invention, the following vertical, longitudinal, and transverse directions along the markers V, L, and T shown in each figure are adopted non-limitingly, based on convention and without limiting reference to other criteria such as gravity. The longitudinal axis L and the vertical axis V extend on the planes of Figures 1 and 2.
[0044] - The longitudinal direction L is the direction in which the eyes of the person who wants to concentrate are aligned. This also determines the lateral position (the lateral position of the person along the longitudinal direction as shown in Figure 5), and this longitudinal direction is considered horizontal when the person is standing upright with their head aligned with the vertical axis.
[0045] - The vertical direction V is perpendicular to the longitudinal direction on the planes of Figures 1 and 2 (determining positions such as upward, downward, top, and bottom).
[0046] - The transverse direction T, which also determines the inner position, is the direction towards the person you want to focus on, the outer position is the position opposite the inner position, that is, the position facing forward of the person, that is, the front position facing the person as shown in Figure 4, and the front position facing the device according to the present invention as shown in Figure 3, and the rear position is the position opposite the front position. [Brief explanation of the drawing]
[0047] [Figure 1] This is a schematic front view of one embodiment of the device of the present invention, laid out in a planar state, before being attached around the head of a person who wants to concentrate or who needs to be helped to concentrate. [Figure 2] Figure 1 is a schematic rear view of an embodiment of the present invention. [Figure 3] Figures 4 and 5 show a schematic frontal perspective view of the same embodiment of the device of the present invention as shown in Figures 1 and 2, but in a closed position when worn around the head of a person who wants to concentrate or who is being asked to concentrate. [Figure 4] Figures 1 to 3 show the same embodiment of the device of the present invention, which is mounted around the head of a person who wants to concentrate or who is being asked to concentrate, and is in a closed position as shown in Figure 3. These are schematic front perspective views. [Figure 5] Figure 4 shows a schematic side perspective view of the same embodiment of the device of the present invention as shown in Figures 1 to 4, with the device attached around the head of a person who wants to concentrate or who is being asked to concentrate, in a closed position. [Figure 6] This is a diagram of the same device as in Figure 1, but without the displays and pictograms. [Figure 7] This is a diagram of the same device as in Figure 3, but without the displays and pictograms. [Figure 8] This is a partial view of the same apparatus as Figure 2, with a cross-sectional view along axis AA. [Figure 9]This is a diagram of the same device as in Figure 5, but without the labels or pictograms, showing the left eye, left ear, and forehead of a person wearing it, as well as the contact band used to keep it away from the forehead. [Figure 10] This is a diagram of the same device as in Figure 4, but without the displays and pictograms, showing a person wearing the device and being able to see through the pads and contact bands. [Modes for carrying out the invention]
[0048] In this description, identical, similar, or identical elements are given the same reference number.
[0049] The concentration support device 100, which assists the concentration of person 12, includes a headband 1 capable of surrounding the forehead and head 13 of person 12, regardless of the embodiment of the present invention. - A central cutout 3 is intended to be positioned in front of the eyes of person 12, and to secure the field of view 10 in front of it, - Two protrusions 41, 42 surrounding both sides of the notch 3, which are intended to cover, if not block, the ears of person 12, and which form two eye shields capable of restricting the lateral field of view 10 of person 12 to an angle of up to 80 degrees symmetrically from person 12, i.e., the midline plane of the device and It is equipped with.
[0050] The central notch 3 is defined by an upper edge 30 extending substantially parallel to the longitudinal direction L, and two side edges 31 and 32 positioned on the left and right sides of the midline plane of each portion 12. The side edges 31 and 32 form the edges of the protrusions 41 and 42. The upper edge 30 and the two side edges 31 and 32 together determine the curved or bent edge line of an inverted "U" shape.
[0051] The top edge 30 can be straight or curved and extends between the top edge 30 and two curved sections 33 and 34 that bend between the top edge 30 and each side edge 31 and 32. The side edges 31 and 32 extend along a direction inclined at 90 to 135 degrees with respect to the longitudinal direction L.
[0052] As shown in Figure 7, the length L30 of the top edge 30, measured along the longitudinal direction L (between the two curved sections 33 and 34), can be 8 to 12 centimeters. The lengths L31 and L32 of the side edges 31 and 32 can both be the same, 5 to 10 centimeters.
[0053] In the following description of the embodiments, the headband 1 according to the present invention is - On the other hand, there is a part 11 made of a flexible sheet of plastic material with an elongated shape along the longitudinal direction L as defined earlier, in which the central part having a relatively narrow width l3 along the direction V forms a notch, and the two sides having a relatively wide width l4 form protrusions 41, 42 that can cover a person's ears and form two eye shields, - On the other hand, there is a fixing system 2 that connects both ends of the part 11 and can hold the part around the head of person 12. It consists of.
[0054] In another possible embodiment, which is not described here, the headband 1 can be pre-molded in various sizes to fit a given head circumference, for example, like a hat or helmet. In that case, the device 100 is worn over the head of person 12, like a hat or helmet.
[0055] The headband 1 has an inner surface 15 intended to be positioned facing the forehead and temples of a person 12, and an outer surface 16 facing the inner surface 15, which is intended to be visible from the outside. In the following description, the outer surface 15 of the headband 1 is identified with the outer surface of part 11 and the outer surface of device 10, and similarly, the inner surface 16 of the headband 1 is identified with the inner surface of part 11 and the inner surface of device 10.
[0056] The width 14 of the protruding parts 41 and 42 (corresponding to the maximum width of part 11 as described above) is 10 to 20 centimeters each, and can be, for example, 13 to 18 centimeters. The width l3 above the central cutout 3 of the headband (corresponding to the minimum width of part 11 as described above) can be 2 to 8 centimeters.
[0057] The headband 1 has a lower edge 17 with a central notch 3, which faces downwards toward the nose side of the person 12, and the headband also has an upper edge 18 opposite the lower edge 17, which faces upwards toward the forehead side of the person 12. In the following description, the lower edge 17 of the headband 1 is considered identical to the lower edge of part 11, and the upper edge 118 of the headband 1 is considered identical to the upper edge 18 of part 11.
[0058] Figure 1 is a schematic diagram of the outer surface 16 of one embodiment of the device 100 according to the present invention. The headband 1, when unfolded on a flat surface, consists of a component 11 made of a long, narrow, flexible sheet. At least one word 81, 82 expressing silence, such as "chut" as shown in each drawing, is displayed on at least its outer surface 16, and this word may be repeated twice. In that case, this word is placed at least on both sides of a pictogram 9 that also expresses silence, such as a "smiley face" 93 located above the central cutout 3, as shown in each drawing.
[0059] As shown in Figure 1, the two protrusions 41 and 42 can each be provided with graphics 71 and 72 on their outer surface 16 that indicate concentration, i.e., graphics that signify at least partial obstruction of vision, such as a picture of an open hand with the back of the hand facing forward, as shown as an example. - These graphics 71, 72 are necessarily opaque and, if the flexible sheet forming part 11 is transparent, and if the height of these graphics 71, 72 is insufficient for the protrusions 41, 42 to act as blinders, they are necessarily combined with an opaque occluding element located below, or - If part 11 itself is opaque, these graphics 71 and 72 only need to be stylized and do not need to be combined with additional opaque occlusion elements, such as those supplementarily represented in each drawing.
[0060] As shown in the diagram, other pictograms 91 and 92, which are of the same type as the pictogram located above the central cutout 3 but preferably smaller in size, such as a smiley face, can also be displayed below the graphics 71 and 72 that represent concentration, such as hands, near the lower edge 17 of each protrusion 41 and 42.
[0061] Each of the aforementioned markings can be printed directly onto the component 11, or printed on a sticker or sheet and then affixed or laminated onto the component 11.
[0062] Figure 2 is a schematic rear view (i.e., the inner surface 15 side) of the same embodiment as the device 100 shown in Figure 1. This inner surface 15 of the headband 1 is the surface intended to be positioned facing the forehead and temples of a person 12. As can be seen in Figure 2, the device 100 includes a contact band 5 positioned facing this inner surface 15 of the headband 1 (or part 11) and near the upper edge 18 of the headband 1, at least above the notch 3. Referring to Figures 8 and 9, the width E5 of this contact band 5 is, for example, 1 to 4 centimeters, particularly 1.5 to 2.5 centimeters.
[0063] In this way, the contact band 5 allows the headband 1 to be separated from the person's 12 forehead by a distance corresponding to the thickness E5. In this manner, the contact band 5 prevents the headband 1 from being in close contact with the forehead, that is, from being too close to the eyes, and thus, together with the central cutout 3, a clear field of view 10 is secured.
[0064] The contact band 5 is preferably made of foam so that it can be compressed, thereby increasing comfort when the device 100 and the person's forehead come into contact, and also allowing the headband 1 to be kept away from the forehead. The contact band 5 extends along the upper edge 18 of the headband 1 for a predetermined length (which can be 5 to 15 centimeters).
[0065] On the other hand, in a preferred embodiment, the device 100 may be equipped with flexible pads 6 on the protrusions 41, 42. These pads 6 can be attached or made detachable by fastening two parts together, for example, with a hook-and-loop of the "Velcro" type. The purpose is to optimally cover the ears of the person wearing the device.
[0066] These pads 6 can be made of foam and are intended to be placed over the ears of person 12, thereby reducing the perception of noise that may occur around person 12. According to one possibility, these pads 6 are attached to a base that holds the foam pads over the ears. These bases can be made of plastic material, such as injection-molded plastic.
[0067] The headband 1 includes any known type of length-adjustable fastening system 2, which is elongated in shape and connects both ends of component 11. The fastening system 2 may consist of two parts 21, 22, as shown in Figures 1 and 2, each of which is fixed to the upper end of component 11, and these upper ends can be connected to each other when the device is set around the head 13 of person 12, allowing for desired tightening at the back of the head and adjusting the length of the fastening system 2 to fit the head size.
[0068] Figure 3 is a front perspective view of the embodiment of the apparatus 100 shown in Figures 1 and 2, in the closed position.
[0069] In Figures 4 and 10, the device 100 is depicted in a closed position, again from the front, but this time it is shown placed around the head of a person 12 who wants to concentrate on a desk activity, such as reading a document 14 placed in front of them, or who wants to be helped to concentrate. Figure 10 shows that the headband 1 is set on the head 13 of person 12 so that the top edge 30 is positioned above the line of sight axis 120 during use. Both of person 12's eyes are aligned on this line of sight axis 120, which is parallel to the longitudinal direction L. More specifically, the top edge 30 is positioned at a predetermined distance D2 above the line of sight axis 120, and this distance D2 is a maximum of 3 centimeters, for example, 1 to 2 centimeters. This distance D2 is also shown in Figure 9.
[0070] The device 100 depicted in Figures 5 and 9 is in the closed position and, like in Figures 4 and 10, is attached to the head of person 12. However, this is a side view and illustrates the position of the protrusions 41 and 42 facing person 12's ears, which also serve as an eye patch that limits the field of view 10 to a width just sufficient for reading the document 14, as well as the isolation of the headband 1 from the forehead achieved by the contact band 5 with a thickness of E5, as previously explained.
[0071] Finally, the device 100 is equipped with a notch (not shown) that can receive a label for customizing the device, such as the name of the person 12 who will be using it.
Claims
1. A concentration support device (100) for assisting a person (12) in concentrating, wherein the concentration support device (100) includes a headband (1) capable of surrounding the forehead and head (13) of the person (12), and the headband (1) has an inner surface (15) intended to be positioned facing the forehead and temples of the person (12), and an outer surface (16) facing the inner surface, - A central notch (3) intended to be positioned in front of the person (12), - Two protrusions (4) surrounding both sides of the central notch (3), which are intended to be placed over the ears of the person (12) and cover the ears. 1 , 4 2 )and Equipped with, The concentration support device (100) includes a contact band (5) located on the inner surface (15) of the headband (1) at least above the central notch (3), which can move the headband (1) away from the forehead of the person (12), and as a result, the contact band (5), together with the central notch (3), enables the securing of a forward field of view (10), and the field of view (10) forms two eye-blocking strips which can restrict the lateral field of view (10), and the two protrusions (4 1 , 4 2 A concentration support device (100) that is constrained laterally by ).
2. The headband (1) - On the other hand, a part (11) made from a flexible sheet with an elongated shape, having a relatively narrow width (l 3 The central part of which has ) constitutes the central cutout (3), and has a relatively wide width (l 4 ) has the protruding portion (4 1 , 4 2 The components (11) that make up the ) - On the other hand, when the part (11) is shaped to surround the head (13) of the person (12), a fixing system (2) connects both ends of the part (11) and A concentration support device (100) according to claim 1, comprising the above.
3. The concentration support device (100) according to claim 2, wherein the flexible sheet (11) is made of a plastic material.
4. The concentration support device (100) according to claim 2 or 3, wherein the fixing system (2) connecting both ends of the component (11) is adjustable in length.
5. The concentration support device (100) according to any one of claims 1 to 4, comprising a flexible pad (6) located on the inner surface (15) of the headband (1) and on the protruding portion (4).
6. A concentration support device (100) according to any one of claims 1 to 5, comprising a notch capable of receiving a label for customization of the device.
7. The concentration support device (100) according to any one of claims 1 to 6, wherein the thickness (E5) of the contact band (5) is 1 to 4 centimeters, for example, 1.5 to 2.5 centimeters.
8. The concentration support device (100) according to any one of claims 1 to 7, wherein the contact band (5) is made at least partially of a foam material.
9. The concentration support device (100) according to any one of claims 1 to 8, wherein the headband (1) has a lower edge (17) on which the central notch (3) is provided and an upper edge (18) opposite to the lower edge (17), and the contact band (5) is arranged along the upper edge (18).
10. The central notch (3) has an upper side (30) and two side edges (31) each contacting the two protruding portions (4 1 , 4 2 ), and the concentrated force assisting device (100) according to any one of claims 1 to 9, defined by
11. The concentration support device (100) according to claim 10, wherein the length (L30) of the upper side (30) is 8 to 12 centimeters.
12. The concentration support device (100) according to claim 10 or 11, wherein the lengths (L31, L32) of the two sides (31, 32) are each 5 to 10 centimeters.
13. The concentration support device (100) according to any one of claims 1 to 12, wherein the central notch (3) is defined by curved or bent side lines that form an overall inverted "U" shape.
14. The protruding portion (4 1 , 4 2 ) width (l 4 The concentration support device (100) according to any one of claims 1 to 13, wherein each of the dimensions is 10 to 20 centimeters, for example, 13 to 18 centimeters.
15. Use of the concentration support device (100) according to any one of claims 1 to 14, wherein the central notch (3) is positioned in front of the eyes of the person (12), and the contact band (5) is positioned facing the forehead in order to keep the headband (1) away from the forehead of the person (12) and secure a forward field of view (10), so that the headband (1) surrounds the forehead and head (13) of the person (12), and the field of view (10) is the two protrusions (4 1 , 4 2 Usage is restricted laterally by ).
16. The use according to claim 15, wherein the central notch (3) is defined by the upper edge (30), the eyes of the person (12) are aligned along the line of sight axis (120), and the headband (1) is positioned on the head (13) of the person (12) such that the upper edge (30) is positioned above the line of sight axis (120).
17. The use according to claim 16, wherein the upper edge (30) is located at a predetermined distance (D2) above the line of sight axis (120), and the distance (D2) is a maximum of 3 centimeters, for example, 1 to 2 centimeters.