How to set up Grafana so that no password is necessary to view dashboards

Thanks @Donald Mok for his answer; I just want to make it as clear as possible. In the Grafana interface you can create an organization. After that you can create some dashboards for this organization. So, there is a problem that you need to specify the organization for anonymous users. And it should be a real organization (for your Grafana). And anonymous users will be able to see only dashboards from this organization.

#################################### Anonymous Auth ##########################
[auth.anonymous]
# enable anonymous access
enabled = true

# specify organization name that should be used for unauthenticated users
org_name = ORGANIZATION

To setup login for anonymous users you need to make these small configuration changes in the default.ini/grafana.ini file (Grafana\conf).

1. If you want to hide the login page do this configuration:

   [auth]
   # Set to true to disable (hide) the login form, useful if you use OAuth
   #disable_login_form = false 
   disable_login_form = true
   

   Change disable_login_form to true.

2. Enable anonymous access:

   [auth.anonymous]
   # enable anonymous access 
   enabled = true
   

3. Specify the organization:

   # specify organization name that should be used for unauthenticated users
   org_name = YOUR_ORG_NAME_HERE
   

4. Restart Grafana and you should be able to see the Grafana dashboard. If not, just change your org role from Viewer to Editor:

   # specify role for unauthenticated users
   org_role = Editor